WO2016002902A1 - Method for producing passivation layer formation composition, semiconductor substrate provided with passivation layer, method for producing same, solar cell element, method for producing same, and solar cell - Google Patents

Abstract

This method for producing a passivation layer formation composition includes a step for preparing a mixed composition by mixing a liquid medium and the compound represented by general formula (I), and a step for preparing a water-containing composition by mixing water and the mixed composition. General formula (I): M(OR¹)_m (in general formula (I): M represents at least one component selected from the group consisting of Al, Nb, Ta, VO, Y, and Hf; R¹ each represents an alkyl group or an aryl group; and m represents an integer from 1 to 5).

Description

Method for producing composition for forming passivation layer, semiconductor substrate with passivation layer and method for producing the same, solar cell element and method for producing the same, and solar cell

The present invention relates to a method for manufacturing a composition for forming a passivation layer, a semiconductor substrate with a passivation layer and its manufacturing method, a solar cell element and its manufacturing method, and a solar cell.

The manufacturing process of the conventional silicon solar cell element is demonstrated.
A texture structure is formed on the front surface (light-receiving surface and / or back surface) of the p-type silicon substrate so as to promote the light confinement effect and increase the efficiency. Subsequently, a treatment for several tens of minutes is performed at 800 ° C. to 900 ° C. in a mixed gas atmosphere of phosphorus oxychloride (POCl ₃ ), nitrogen and oxygen to form an n-type diffusion layer uniformly on the surface of the p-type silicon substrate. . The n-type diffusion layer formed on the side surface of the p-type silicon substrate is removed by side etching or the like. In addition, the n-type diffusion layer formed on the back surface of the p-type silicon substrate needs to be converted into a p ⁺ -type diffusion layer. Therefore, an aluminum paste containing aluminum powder and a binder is applied to the entire back surface, and this is heat-treated (fired) to convert the n-type diffusion layer into a p ⁺ -type diffusion layer called BSF (Back Surface Field). At the same time, an ohmic contact is obtained by forming an aluminum electrode.

However, an aluminum electrode formed from an aluminum paste has low conductivity. For this reason, in order to reduce the sheet resistance, the aluminum electrode generally formed on the entire back surface must have a thickness of about 10 μm to 20 μm after heat treatment (firing). However, since the thermal expansion coefficient differs greatly between silicon and aluminum, a large internal stress is generated in the silicon substrate during the heat treatment (firing) and cooling in the silicon substrate on which the aluminum electrode is formed, and the grain boundary Cause damage, crystal defect growth, and warping. In addition, since the Al—Si alloy formed at the interface between the BSF or the aluminum electrode and silicon has light absorption, this alloy layer is a major factor for reducing the power generation efficiency.
As a technique for solving these problems, Japanese Patent No. 3107287 discloses a point contact technique in which an aluminum paste is applied to a part of a silicon substrate surface to partially form a p ⁺ -type diffusion layer and an aluminum electrode. Proposed.
In the case of a solar cell having a point contact structure on the surface opposite to the light receiving surface (hereinafter also referred to as “back surface”), it is necessary to suppress the recombination rate of minority carriers on the surface of the portion other than the aluminum electrode. is there. As a back surface passivation layer for that purpose, Japanese Patent Application Laid-Open No. 2004-6565 proposes a SiO ₂ film or the like. As a passivation effect by forming such a SiO ₂ film, there is an effect of terminating the dangling bonds of silicon atoms in the back surface layer portion of the silicon substrate and reducing the surface state density causing recombination. .

As another method of suppressing recombination of minority carriers, there is a method of reducing the minority carrier density by an electric field that generates fixed charges in the passivation layer. Such a passivation effect is generally called a field effect, and an aluminum oxide (Al ₂ O ₃ ) film or the like is proposed in Japanese Patent No. 4767110 as a material having a negative fixed charge.
Such a passivation layer is generally formed by ALD (Atomic Layer Deposition) method, CVD (Chemical Vapor Deposition) method, etc. as described in Journal of Applied Physics, 104 (2008), 113703-1 to 113703-7. It is formed by the method. Further, as a simple method for forming an aluminum oxide film on a semiconductor substrate, Thin Solid Films, 517 (2009), 6327-6330 and Chinese Physics Letters, 26 (2009), 088102-1 to 088102-4 include sol-gel. A method by law has been proposed.

The methods described in Journal of Applied Physics, 104 (2008), 113703-1 to 113703-7 include complicated manufacturing processes such as vapor deposition, and thus it may be difficult to improve productivity. In addition, the composition for forming a passivation layer used for the methods described in Thin Solid Films, 517 (2009), 6327-6330 and Chinese Physics Letters, 26 (2009), 088102-1 to 088102-4 is gelated over time. It is difficult to say that the storage stability is sufficient. Further, since a predetermined pattern cannot be formed by these methods, a step of forming a passivation layer pattern by etching a portion where an aluminum electrode is to be formed by laser, photolithography or the like after forming a passivation layer. Is required.

One embodiment of the present invention has been made in view of the above-described conventional problems, and is for forming a passivation layer capable of forming a passivation layer excellent in pattern formability and excellent in a passivation effect by a simple method. It is an object to provide a method for producing a composition. In addition, one embodiment of the present invention is a semiconductor substrate with a passivation layer obtained using the composition for forming a passivation layer manufactured by the manufacturing method, and having a passivation layer having an excellent passivation effect, a manufacturing method thereof, and It aims at providing the solar cell element which has the outstanding conversion efficiency, the manufacturing method of a solar cell element, and a solar cell.

Specific means for achieving the above object are as follows.
<1> A method for producing a composition for forming a passivation layer comprising the following steps (1) and (2).
(1) A step of mixing a compound represented by the following general formula (I) and a liquid medium to produce a mixed composition.
(2) A step of mixing the mixed composition and water to produce a water-containing composition.
M (OR ¹ ) _m (I)
[In General Formula (I), M represents at least one selected from the group consisting of Al, Nb, Ta, VO, Y, and Hf. R ¹ independently represents an alkyl group or an aryl group. m represents an integer of 1 to 5. ]

<2> The compound represented by the following general formula (II) is mixed with the compound represented by the general formula (I) and the liquid medium in the step (1), or the compound represented by (2) The method for producing a passivation layer forming composition according to <1>, wherein the composition is mixed with the water-containing composition after the step.

 

 

[In General Formula (II), each R ² independently represents an alkyl group. n represents an integer of 1 to 3. X ² and X ³ each independently represent an oxygen atom or a methylene group. R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group. ]

<3> A method for producing a composition for forming a passivation layer comprising the following steps (3) and (4).
(3) A step of preparing a water-containing liquid medium by mixing a liquid medium and water.
(4) A step of preparing a water-containing composition by mixing the water-containing liquid medium and a compound represented by the following general formula (I).
M (OR ¹ ) _m (I)
[In General Formula (I), M represents at least one selected from the group consisting of Al, Nb, Ta, VO, Y, and Hf. R ¹ independently represents an alkyl group or an aryl group. m represents an integer of 1 to 5. ]

<4> The compound represented by the following general formula (II) is mixed with the compound represented by the general formula (I) and the water-containing liquid medium in the step (4), or (4) The method for producing a composition for forming a passivation layer according to <3>, wherein the composition is mixed with the water-containing composition after the step.

 

 

[In General Formula (II), each R ² independently represents an alkyl group. n represents an integer of 1 to 3. X ² and X ³ each independently represent an oxygen atom or a methylene group. R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group. ]

<5> The composition for forming a passivation layer according to <1> or <2>, wherein the mixed composition has a shear viscosity of 0.1 Pa · s or more under conditions of 25.0 ° C. and a shear rate of 10 s ⁻¹ . Manufacturing method.

<6> The method for producing a passivation layer forming composition according to any one of <1> to <5>, wherein the liquid medium includes a compound represented by the following general formula (III).

 

 

<7> The addition rate of water when the total of the compound represented by the general formula (I) and the compound represented by the general formula (II) used as necessary is 100 mol% is 50 mol. The method for producing a composition for forming a passivation layer according to any one of <1> to <6>, wherein the composition is% to 2000 mol%.

<8> a semiconductor substrate;
A passivation layer which is provided on at least a part of at least one surface of the semiconductor substrate and is a heat treatment product of the passivation layer forming composition manufactured by the manufacturing method according to any one of <1> to <7>. When,
A semiconductor substrate with a passivation layer.

<9> A composition layer obtained by applying a composition for forming a passivation layer produced by the production method according to any one of <1> to <7> to at least a part of at least one surface of a semiconductor substrate. Forming a step;
Heat-treating the composition layer to form a passivation layer;
The manufacturing method of the semiconductor substrate with a passivation layer which has this.

<10> a semiconductor substrate having a pn junction part in which a p-type layer and an n-type layer are pn-junction;
A passivation layer which is provided on at least a part of at least one surface of the semiconductor substrate and is a heat treatment product of the passivation layer forming composition manufactured by the manufacturing method according to any one of <1> to <7>. When,
An electrode disposed on at least one of the p-type layer and the n-type layer;
A solar cell element having

<11> The production according to any one of <1> to <7>, wherein at least part of at least one surface of a semiconductor substrate having a pn junction formed by pn junction of a p-type layer and an n-type layer. Providing a composition for forming a passivation layer produced by the method to form a composition layer; and
Heat-treating the composition layer to form a passivation layer;
Disposing an electrode on at least one of the p-type layer and the n-type layer;
The manufacturing method of the solar cell element which has this.

<12> The solar cell element according to <10>,
A wiring material disposed on the electrode of the solar cell element;
A solar cell having:

According to one embodiment of the present invention, it is possible to provide a method for producing a composition for forming a passivation layer capable of forming a passivation layer having an excellent pattern forming property and an excellent passivation effect by a simple technique. Further, according to one embodiment of the present invention, a semiconductor substrate with a passivation layer obtained using the composition for forming a passivation layer manufactured by the manufacturing method and having a passivation layer having an excellent passivation effect, and a manufacturing method thereof And the solar cell element which has the outstanding conversion efficiency, the manufacturing method of a solar cell element, and a solar cell can be provided.

It is sectional drawing which shows typically an example of the manufacturing method of the solar cell element which has a passivation layer which concerns on this embodiment. It is sectional drawing which shows typically another example of the manufacturing method of the solar cell element which has a passivation layer which concerns on this embodiment. It is sectional drawing which shows typically another example of the manufacturing method of the solar cell element which has a passivation layer which concerns on this embodiment. It is a schematic plan view which shows an example of the light-receiving surface of the solar cell element of this embodiment. It is a schematic plan view which shows an example of the formation pattern in the back surface of the passivation layer which concerns on this embodiment. It is a schematic plan view which shows another example of the formation pattern in the back surface of the passivation layer which concerns on this embodiment. It is the schematic plan view to which the A section of FIG. 5 was expanded. It is the schematic plan view to which the B section of FIG. 5 was expanded. It is a schematic plan view which shows an example of the back surface of the solar cell element of this embodiment. It is a figure for demonstrating an example of the manufacturing method of the solar cell of this embodiment.

Hereinafter, the manufacturing method of the composition for forming a passivation layer of the present invention, the semiconductor substrate with a passivation layer and the manufacturing method thereof, the solar cell element and the manufacturing method thereof, and the form for carrying out the solar cell will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the components (including element steps and the like) are not essential unless otherwise specified. The same applies to numerical values and ranges thereof, and the present invention is not limited thereto.
In this specification, the term “process” is not limited to an independent process, and is included in this term if the purpose of the process is achieved even when it cannot be clearly distinguished from other processes. A numerical range indicated by using “to” indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively. Furthermore, the content of each component in the composition is the total amount of the plurality of substances present in the composition unless there is a specific indication when there are a plurality of substances corresponding to each component in the composition. means. In addition, in the present specification, the term “layer” includes a configuration of a shape formed in part in addition to a configuration of a shape formed on the entire surface when observed as a plan view.

<Method for producing composition for forming passivation layer>
The method for producing the first passivation layer forming composition of the present embodiment (hereinafter sometimes referred to as the first production method) includes the following steps (1) and (2).
(1) A step of preparing a mixed composition by mixing a compound represented by the following general formula (I) (hereinafter sometimes referred to as a compound of formula (I)) and a liquid medium.
(2) A step of mixing the mixed composition and water to produce a water-containing composition.
Moreover, the manufacturing method (henceforth a 2nd manufacturing method) of the 2nd composition for passivation layer formation of this embodiment includes the process of following (3) and following (4).
(3) A step of preparing a water-containing liquid medium by mixing a liquid medium and water.
(4) A step of preparing a water-containing composition by mixing the water-containing liquid medium and a compound represented by the following general formula (I).
The first manufacturing method and the second manufacturing method may be collectively referred to as the manufacturing method of this embodiment.

M (OR ¹ ) _m (I)
In general formula (I), M represents at least one selected from the group consisting of Al, Nb, Ta, VO, Y, and Hf. R ¹ independently represents an alkyl group or an aryl group. m represents an integer of 1 to 5.

As a result of intensive studies, the present inventor has found that although the mechanism is not clear, the thixotropy of the composition is improved by allowing water to act on the compound of formula (I).
The composition for forming a passivation layer produced by the production method of the present embodiment contains the compound of formula (I) and water, and the passivation layer is formed by allowing water to act on the compound of formula (I). The thixo ratio of the forming composition is improved. As a result, it is surmised that the composition for forming a passivation layer produced by the production method of the present embodiment is excellent in pattern formability.
The composition for forming a passivation layer produced by the production method of this embodiment is improved in its thixotropy by allowing water to act on the compound of formula (I), and the composition for forming a passivation layer is imparted on a semiconductor substrate. Thus, the shape stability of the formed composition layer is further improved, and the passivation layer can be formed in a desired shape in the region where the composition layer is formed. Therefore, in the composition for forming a passivation layer produced by the production method of the present embodiment, at least one of a thixotropic agent and a resin described later (hereinafter, at least one of the thixotropic agent and the resin is thixotropic) in order to express desired thixotropic properties. Even if a thixotropic agent or the like is used, the amount added can be reduced as compared with the conventional passivation layer forming composition.
When forming a passivation layer using a composition for forming a passivation layer containing a thixotropic agent composed of an organic substance, the thixotropic agent is thermally decomposed and scattered from the passivation layer through a degreasing process. Become. However, a thermal decomposition product such as a thixotropic agent may remain as an impurity in the passivation layer even after the degreasing step, and the remaining thermal decomposition product such as a thixotropic agent may cause deterioration of the characteristics of the passivation layer. On the other hand, when forming a passivation layer using a composition for forming a passivation layer containing a thixotropic agent composed of an inorganic substance, the thixotropic agent does not scatter and remains in the passivation layer even after a heat treatment (firing) step. The remaining thixotropic agent may cause deterioration of the characteristics of the passivation layer.
On the other hand, in the composition for forming a passivation layer produced by the production method of this embodiment, water or a hydrolyzate of the compound of formula (I) behaves as a thixotropic agent when water acts on the compound of formula (I). Water is more likely to scatter from the passivation layer than a conventional thixotropic agent or the like in a heat treatment (firing) step or the like that is performed when the passivation layer is formed using the passivation layer forming composition. For this reason, it is difficult to cause a decrease in the passivation effect of the passivation layer due to the presence of the residue in the passivation layer.

Further, when the compound of formula (I) and water are directly mixed, the contacted portion is hydrolyzed and a hydrolyzate is formed as disclosed in JP-A-10-139788. This hydrolyzate may aggregate and easily form a solid, and it may be difficult for the compound of formula (I) itself to be uniformly dispersed in an organic solvent or the like.
Therefore, in order to make it difficult to cause aggregation of the hydrolyzate, it is preferable to mix water in a state where the compound (I) is uniformly dispersed in a high-viscosity liquid medium to obtain a mixed composition. The hydrolyzate is not easily aggregated in a high-viscosity liquid medium. Therefore, in the first production method, a composition for forming a passivation layer with less mixing unevenness is provided. Furthermore, since uniform gelation proceeds as a whole including the liquid medium, a paste having a large thixotropy can be obtained.
On the other hand, in order to prevent the direct contact between the compound of formula (I) and water, the liquid medium and water are mixed and hydrated in the liquid medium, and then the hydrated liquid medium and the compound of formula (I) are mixed. You may mix. By mixing the water-containing liquid medium and the compound of formula (I), the presence of the liquid medium prevents direct contact between the compound of formula (I) and water, and the generation of hydrolyzate can be suppressed. Therefore, in the second production method, a composition for forming a passivation layer with less mixing unevenness is provided. Furthermore, since uniform gelation proceeds as a whole including the liquid medium, a paste having a large thixotropy can be obtained.

In this specification, the passivation effect of a semiconductor substrate refers to an effective lifetime of minority carriers in a semiconductor substrate on which a passivation layer is formed by using reflected light photoconductive attenuation using a device such as Nippon Semi-Lab Co., Ltd. or WT-2000PVN. It can be evaluated by measuring by the method.

Here, the effective lifetime τ is expressed by the following equation (A) by the bulk lifetime τb inside the semiconductor substrate and the surface lifetime τs on the surface of the semiconductor substrate. When the surface state density on the surface of the semiconductor substrate is small, τs becomes long, resulting in a long effective lifetime τ. Further, even if defects such as dangling bonds in the semiconductor substrate are reduced, the bulk lifetime τb is increased and the effective lifetime τ is increased. That is, by measuring the effective lifetime τ, the interface characteristics between the passivation layer and the semiconductor substrate and the internal characteristics of the semiconductor substrate such as dangling bonds can be evaluated.

1 / τ = 1 / τb + 1 / τs (A)

In addition, it shows that the recombination rate of minority carriers is so small that effective lifetime (tau) is long. Moreover, conversion efficiency improves by comprising a solar cell element using the semiconductor substrate with a long effective lifetime.
However, since the lifetime depends on the specific resistance, thickness, and surface state of the semiconductor substrate, the passivation effect of the passivation layer may not always be measured correctly. Therefore, as another method for examining the passivation effect of the semiconductor substrate, there is a method of evaluating a fixed charge of the passivation layer by using a CV method (Capacitance Voltage measurement). When a large fixed charge is present in the passivation layer, recombination of minority carriers on the surface is suppressed, so that the recombination rate of minority carriers is reduced.

(Compound represented by formula (I))
In the production method of this embodiment, at least one compound of the formula (I) is used. When the composition for forming a passivation layer contains at least one compound of the formula (I), a passivation layer having an excellent passivation effect can be formed. The reason can be considered as follows.

A metal oxide formed by heat-treating (firing) a composition for forming a passivation layer produced using a compound of formula (I) has defects of metal atoms or oxygen atoms and tends to generate fixed charges. Conceivable. This fixed charge can generate a charge in the vicinity of the interface with the semiconductor substrate, thereby reducing the concentration of minority carriers. As a result, the carrier recombination rate at the interface is suppressed, and an excellent passivation effect is achieved. it is conceivable that.

Here, regarding the state of the passivation layer that generates a fixed charge on the semiconductor substrate, the cross section of the semiconductor substrate is subjected to electron energy loss spectroscopy (EELS, Electron Energy Loss Spectroscopy) using a scanning transmission electron microscope (STEM, Scanning Transmission Electron Microscope). It can be evaluated by examining the binding mode in the analysis of). Further, by measuring an X-ray diffraction spectrum (XRD, X-ray diffraction), the crystal phase near the interface of the passivation layer can be confirmed.

In the general formula (I), M represents at least one selected from the group consisting of Al, Nb, Ta, VO, Y, and Hf. Two or more types of M may be contained in the compound of the formula (I).
In the general formula (I), each R ¹ independently represents an alkyl group or an aryl group, preferably an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 14 carbon atoms, and an alkyl group having 1 to 8 carbon atoms. Is more preferable, and an alkyl group having 1 to 4 carbon atoms is still more preferable. The alkyl group represented by R ¹ may be linear or branched.

Specific examples of the alkyl group represented by R ¹ include methyl, ethyl, propyl, i-propyl, butyl, i-butyl, sec-butyl, t-butyl, hexyl, and octyl. Group, 2-ethylhexyl group, 3-ethylhexyl group and the like.
Specific examples of the aryl group represented by R ¹ include a phenyl group.
The alkyl group and aryl group represented by R ¹ may have a substituent, and examples of the substituent of the alkyl group include an amino group, a hydroxy group, a carboxy group, a sulfo group, and a nitro group. Examples of the substituent for the aryl group include a methyl group, an ethyl group, an i-propyl group, an amino group, a hydroxy group, a carboxy group, a sulfo group, and a nitro group.
Among these, R ¹ is preferably an unsubstituted alkyl group having 1 to 8 carbon atoms, more preferably an unsubstituted alkyl group having 1 to 4 carbon atoms, from the viewpoints of reactivity with water and a passivation effect. preferable.

In the general formula (I), m represents an integer of 1 to 5. Here, from the viewpoint of reactivity with water, m is preferably 3 when M is Al, m is preferably 5 when M is Nb, and M is Ta. In some cases, m is preferably 5, m is preferably 3 when m is VO, m is preferably 3 when M is Y, and M is Hf. In this case, m is preferably 4.

In the compound of formula (I), M is at least one selected from the group consisting of Nb, Ta, VO and Hf, R ¹ is an unsubstituted alkyl group having 1 to 4 carbon atoms, and m is An integer of 1 to 5 is preferable.

The state of the compound of formula (I) may be solid or liquid at 25 ° C. From the viewpoint of storage stability of the composition for forming a passivation layer, miscibility with water, and miscibility in the case where a compound represented by formula (II) described later is used in combination, the compound of formula (I) is liquid at 25 ° C. It is preferable that

The compounds of formula (I) are specifically aluminum methoxide, aluminum ethoxide, aluminum i-propoxide, aluminum n-propoxide, aluminum n-butoxide, aluminum t-butoxide, aluminum i-butoxide, niobium methoxide. Niobium ethoxide, niobium i-propoxide, niobium n-propoxide, niobium n-butoxide, niobium t-butoxide, niobium i-butoxide, tantalum methoxide, tantalum ethoxide, tantalum i-propoxide, tantalum n-propoxy Tantalum n-butoxide, tantalum t-butoxide, tantalum i-butoxide, yttrium methoxide, yttrium ethoxide, yttrium i-propoxide, yttrium n-propoxide, yttrium n-but Sid, Yttrium t-butoxide, Yttrium i-butoxide, Vanadium oxymethoxide, Vanadium oxyethoxide, Vanadium oxy i-propoxide, Vanadium oxy n-propoxide, Vanadium oxy n-butoxide, Vanadium oxy t-butoxide, Vanadium oxy Examples include i-butoxide, hafnium methoxide, hafnium ethoxide, hafnium i-propoxide, hafnium n-propoxide, hafnium n-butoxide, hafnium t-butoxide, hafnium i-butoxide, among others, aluminum ethoxide, Aluminum i-propoxide, aluminum n-butoxide, niobium ethoxide, niobium n-propoxide, niobium n-butoxide, tantalum ethoxide, tantalum n- Ropokishido, tantalum n- butoxide, yttrium i- propoxide, and yttrium n- butoxide are preferred.

In addition, as the compound of formula (I), a prepared product or a commercially available product may be used. Examples of commercially available products include pentamethoxyniobium, pentaethoxyniobium, penta-i-propoxyniobium, penta-n-propoxyniobium, penta-i-butoxyniobium and penta-n-butoxyniobium from High Purity Chemical Laboratory Co., Ltd. , Penta-sec-butoxy niobium, pentamethoxy tantalum, pentaethoxy tantalum, penta-i-propoxy tantalum, penta-n-propoxy tantalum, penta-i-butoxy tantalum, penta-n-butoxy tantalum, penta-sec-butoxy tantalum Penta-t-butoxytantalum, vanadium (V) trimethoxide oxide, vanadium (V) triethoxide oxide, vanadium (V) tri-i-propoxide oxide, vanadium (V) tri-n-propoxide oxide, vanadium( ) Tri-i-butoxide oxide, vanadium (V) tri-n-butoxide oxide, vanadium (V) tri-sec-butoxide oxide, vanadium (V) tri-t-butoxide oxide, tri-i-propoxy yttrium, tri- n-butoxy yttrium, tetramethoxy hafnium, tetraethoxy hafnium, tetra-i-propoxy hafnium, tetra-t-butoxy hafnium, pentaethoxyniobium, pentaethoxy tantalum, pentaboxy tantalum, yttrium-n-butoxide from Hokuko Chemical Co., Ltd. , Hafnium-tert-butoxide, vanadium oxytriethoxide, vanadium oxytrinormal propoxide, vanadium oxytrinormal butoxide, vanadium oxy from Nichia Corporation Triisobutoxide, mention may be made of vanadium oxy-tri secondary butoxide and the like.

The compound of formula (I) is prepared by reacting a specific metal (M) halide with an alcohol in the presence of an inert organic solvent, and further adding ammonia or an amine compound to extract the halogen (specialty). Known manufacturing methods such as Japanese Utility Model Laid-Open No. 63-227593 and Japanese Patent Laid-Open No. 3-291247) can be used.

At least a part of the compound of formula (I) may be contained in the composition for forming a passivation layer as a compound having a chelate structure formed by mixing with a compound having a specific structure having two carbonyl groups described later. The number of carbonyl groups to be chelated is not particularly limited, but when M is Al, the number of carbonyl groups to be chelated is preferably 1 to 3, and when M is Nb, the number of carbonyl groups to be chelated is The number of carbonyl groups to be chelated is preferably 1 to 5 when M is Ta, and the number of carbonyl groups to be chelated is 1 to 3 when M is VO. Preferably, when M is Y, the number of carbonyl groups to be chelated is preferably 1 to 3, and when M is Hf, the number of carbonyl groups to be chelated is preferably 1 to 4. .

The presence of a chelate structure in the compound of formula (I) can be confirmed by a commonly used analytical method. For example, it can be confirmed using an infrared spectrum, a nuclear magnetic resonance spectrum, a melting point, or the like.

The content of the compound of the formula (I) contained in the composition for forming a passivation layer produced by the production method of the present embodiment can be appropriately selected as necessary. The content of the compound of formula (I) can be 0.1% by mass to 80% by mass in the composition for forming a passivation layer from the viewpoint of reactivity with water and a passivation effect, and 0.5% by mass. It is preferably ˜70% by mass, more preferably 1% by mass to 60% by mass, and still more preferably 1% by mass to 50% by mass.

(Compound represented by formula (II))
In the production method of the present embodiment, at least one compound represented by the following general formula (II) (hereinafter also referred to as “organoaluminum compound”) may be used.

 

 

In general formula (II), each R ² independently represents an alkyl group. n represents an integer of 1 to 3. X ² and X ³ each independently represent an oxygen atom or a methylene group. R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group.

When the composition for forming a passivation layer contains the organoaluminum compound, the passivation effect can be further improved. This can be considered as follows.

The organoaluminum compound is a compound called aluminum chelate or the like, and preferably has an aluminum chelate structure in addition to the aluminum alkoxide structure. Also, Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi, vol. 97, pp 369-399 (1989), the organoaluminum compound becomes aluminum oxide (Al ₂ O ₃ ) by heat treatment (firing). At this time, since the formed aluminum oxide is likely to be in an amorphous state, a four-coordinate aluminum oxide layer is easily formed in the vicinity of the interface with the semiconductor substrate, and may have a large negative fixed charge due to the four-coordinate aluminum oxide. It is considered possible. At this time, it is considered that a passivation layer having an excellent passivation effect can be formed by compounding with an oxide derived from the compound of formula (I) having a fixed charge.

In addition to the above, the combination of the compound of formula (I) and the organoaluminum compound is considered to increase the passivation effect due to the respective effects in the passivation layer. Further, a heat treatment (firing) is performed in a state where the compound of formula (I) and the organoaluminum compound are mixed, thereby generating a composite metal alkoxide of metal (M) and aluminum (Al) contained in the compound of formula (I). In addition, it is considered that physical properties such as reactivity and vapor pressure are improved, the denseness of the passivation layer as a heat-treated product (baked product) is improved, and as a result, the passivation effect is further enhanced.

In the general formula (II), each R ² independently represents an alkyl group, preferably an alkyl group having 1 to 8 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms. The alkyl group represented by R ² may be linear or branched. Specific examples of the alkyl group represented by R ² include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, Examples thereof include a hexyl group, an octyl group, a 2-ethylhexyl group, a 3-ethylhexyl group, and the like. Among them, the alkyl group represented by R ² is preferably an unsubstituted alkyl group having 1 to 8 carbon atoms from the viewpoint of storage stability and a passivation effect, and is an unsubstituted alkyl group having 1 to 4 carbon atoms. More preferably.

In the general formula (II), n represents an integer of 1 to 3. n is preferably 1 or 3 from the viewpoint of storage stability, and more preferably 1 from the viewpoint of solubility.
X ² and X ³ each independently represent an oxygen atom or a methylene group. From the viewpoint of storage stability, at least one of X ² and X ³ is preferably an oxygen atom.

R ³ , R ⁴ and R ⁵ in the general formula (II) each independently represent a hydrogen atom or an alkyl group. The alkyl group represented by R ³ , R ⁴ and R ⁵ may be linear or branched. The alkyl group represented by R ³ , R ⁴ and R ⁵ is preferably an alkyl group having 1 to 8 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms. Specific examples of the alkyl group represented by R ³ , R ⁴ and R ⁵ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, and a sec-butyl group. T-butyl group, hexyl group, octyl group, ethylhexyl group and the like. The alkyl group represented by R ³ , R ⁴ and R ⁵ may have a substituent or may be unsubstituted, and is preferably unsubstituted.

Among these, from the viewpoint of storage stability and a passivation effect, R ³ and R ⁴ in the general formula (II) are preferably each independently a hydrogen atom or an unsubstituted alkyl group having 1 to 8 carbon atoms. Or it is more preferably an unsubstituted alkyl group having 1 to 4 carbon atoms.
In addition, R ⁵ in the general formula (II) is preferably a hydrogen atom or an unsubstituted alkyl group having 1 to 8 carbon atoms from the viewpoint of storage stability and a passivation effect, and is preferably a hydrogen atom or 1 to 4 carbon atoms. The unsubstituted alkyl group is more preferable.

From the viewpoint of storage stability, the organoaluminum compound is preferably a compound in which n is an integer of 1 to 3, and R ⁵ is independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

From the viewpoint of storage stability and passivation effect, the organoaluminum compound is such that n is an integer of 1 to 3, R ² is each independently an alkyl group having 1 to 4 carbon atoms, and at least X ² and X ³ One is an oxygen atom, R ³ and R ⁴ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ⁵ is each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. A certain compound is preferable.
More preferably, in the organoaluminum compound, n is an integer of 1 to 3, R ² is each independently an unsubstituted alkyl group having 1 to 4 carbon atoms, and at least one of X ² and X ³ is oxygen R ³ or R ⁴ bonded to the oxygen atom is an alkyl group having 1 to 4 carbon atoms, and when X ² or X ³ is a methylene group, R ³ or R ⁴ bonded to the methylene group is It is a compound which is a hydrogen atom and R ⁵ is a hydrogen atom.

Specific examples of the organoaluminum compound represented by the general formula (II) include aluminum ethyl acetoacetate diisopropylate and tris (ethyl acetoacetate) aluminum.

Further, as the organoaluminum compound represented by the general formula (II), a prepared product or a commercially available product may be used. Examples of commercially available products include trade names of Kawaken Fine Chemical Co., Ltd., ALCH, ALCH-50F, ALCH-75, ALCH-TR, ALCH-TR-20, and the like.

The organoaluminum compound represented by the general formula (II) can be prepared by mixing an aluminum trialkoxide and a compound having a specific structure having two carbonyl groups described later. A commercially available aluminum chelate compound may also be used.

When the aluminum trialkoxide and a compound having a specific structure having two carbonyl groups are mixed, at least a part of the alkoxide group of the aluminum trialkoxide is substituted with the compound having the specific structure to form an aluminum chelate structure. At this time, if necessary, a liquid medium may be present, and heat treatment, addition of a catalyst, or the like may be performed. By replacing at least a part of the aluminum alkoxide structure with the aluminum chelate structure, the stability of the organoaluminum compound to hydrolysis and polymerization reaction is improved, and the storage stability of the composition for forming a passivation layer containing this is further improved. To do.

The compound having a specific structure having two carbonyl groups is at least one selected from the group consisting of β-diketone compounds, β-ketoester compounds, and malonic acid diesters from the viewpoint of reactivity and storage stability. preferable.

Specific examples of β-diketone compounds include acetylacetone, 3-methyl-2,4-pentanedione, 2,3-pentanedione, 3-ethyl-2,4-pentanedione, and 3-butyl-2,4-pentane. Examples include dione, 2,2,6,6-tetramethyl-3,5-heptanedione, 2,6-dimethyl-3,5-heptanedione, 6-methyl-2,4-heptanedione, and the like.

Specific examples of β-ketoester compounds include methyl acetoacetate, ethyl acetoacetate, n-propyl acetoacetate, i-propyl acetoacetate, i-butyl acetoacetate, n-butyl acetoacetate, t-butyl acetoacetate, acetoacetate n-pentyl, i-pentyl acetoacetate, n-hexyl acetoacetate, n-octyl acetoacetate, n-heptyl acetoacetate, 3-pentyl acetoacetate, ethyl 2-acetylheptanoate, ethyl 2-methylacetoacetate, 2-butylacetate Ethyl acetate, ethyl hexyl acetoacetate, ethyl 4,4-dimethyl-3-oxovalerate, ethyl 4-methyl-3-oxovalerate, ethyl 2-ethylacetoacetate, methyl 4-methyl-3-oxovalerate, 3 -Ethyl oxohexanoate, ethyl 3-oxovalerate, methyl 3-oxovalerate, - methyl-oxohexanoate, ethyl 3-oxo heptanoic acid, 3-oxo heptanoic acid methyl, can be mentioned 4,4-dimethyl-3-oxo-valerate, such as methyl.

Specific examples of the malonic acid diester include dimethyl malonate, diethyl malonate, di-n-propyl malonate, di-i-propyl malonate, di-n-butyl malonate, di-t-butyl malonate, and malon. Dihexyl acid, t-butylethyl malonate, diethyl methylmalonate, diethyl ethylmalonate, diethyl i-propylmalonate, diethyl n-butylmalonate, diethyl sec-butylmalonate, diethyl i-butylmalonate, 1-methyl And diethyl butylmalonate.

The number of aluminum chelate structures can be controlled, for example, by appropriately adjusting the mixing ratio of the aluminum trialkoxide and a compound having a specific structure having two carbonyl groups. Moreover, you may select suitably the compound which has a desired structure from a commercially available aluminum chelate compound.

Of the organoaluminum compounds, from the viewpoint of the passivation effect and compatibility with the solvent contained as necessary, specifically, selected from the group consisting of aluminum ethyl acetoacetate di-i-propylate and tri-i-propoxyaluminum It is preferable to use at least one selected from the group consisting of aluminum ethyl acetoacetate di-i-propylate.

The presence of an aluminum chelate structure in the organoaluminum compound can be confirmed by a commonly used analysis method. For example, it can confirm based on an infrared spectroscopy spectrum, a nuclear magnetic resonance spectrum, and melting | fusing point.

The organoaluminum compound may be liquid or solid and is not particularly limited. From the viewpoint of the passivation effect and storage stability, the homogeneity of the formed passivation layer is further improved by using an organoaluminum compound having good stability at room temperature (25 ° C.) and solubility or dispersibility. A desired passivation effect can be stably obtained.

When the composition for forming a passivation layer produced by the production method of the present embodiment contains an organoaluminum compound, the content of the organoaluminum compound is not particularly limited. Among them, the content of the organoaluminum compound is preferably 0.1% by mass to 80% by mass when the total content of the compound of formula (I) and the organoaluminum compound is 100% by mass, % To 80% by weight is more preferable, 1% to 75% by weight is further preferable, 2% to 70% by weight is particularly preferable, and 3% to 70% by weight is preferable. Is very preferred.
By setting the content of the organoaluminum compound to 0.1% by mass or more, the storage stability of the composition for forming a passivation layer tends to be improved. Moreover, it exists in the tendency for the passivation effect to improve by making an organoaluminum compound 80 mass% or less.

When the composition for forming a passivation layer produced by the production method of the present embodiment contains an organoaluminum compound, the content of the organoaluminum compound in the composition for forming a passivation layer can be appropriately selected as necessary. The content of the organoaluminum compound may be 0.1% by mass to 60% by mass in the composition for forming a passivation layer, and 0.5% by mass to 55% by mass from the viewpoint of storage stability and a passivation effect. It is preferably 1% by mass to 50% by mass, more preferably 1% by mass to 45% by mass.

When the composition for forming a passivation layer produced by the first production method contains an organoaluminum compound, the organoaluminum compound is mixed with the compound of formula (I) and a liquid medium in the step (1), or (2) What is necessary is just to mix with a water-containing composition after the process of this.
When the composition for forming a passivation layer produced by the second production method contains an organoaluminum compound, the organoaluminum compound is mixed with the compound of formula (I) and a water-containing liquid medium in the step (4), or (4 It suffices to be mixed with the water-containing composition after the step of).

(Liquid medium)
The liquid medium used in the production method of the present embodiment is not particularly limited as long as the liquid medium has a shear viscosity at 25.0 ° C. of 0.1 Pa · s or more. As the liquid medium that can be used in the present embodiment, a high-boiling material (high-boiling material) that does not need to be easily degassed and degreased during heating may be used.
The shear viscosity of the liquid medium is measured using a rotary shear viscometer equipped with a cone plate (diameter 50 mm, cone angle 1 °) at a temperature of 25.0 ° C. and a shear rate of 10 s ⁻¹ .
In addition, when the shear viscosity of the mixed composition is low in the step (2), an aggregate of the compound of formula (I) may be generated in the water-containing composition when the mixed composition and water are mixed.
The shear viscosity of the mixed composition in which such aggregation does not occur is preferably 0.1 Pa · s or more under the conditions of 25.0 ° C. and a shear rate of 10 s ⁻¹ . More preferably, it is 0.2 Pa · s. The shear viscosity of the mixed composition refers to a value measured in the same manner as the shear viscosity of the liquid medium.
The liquid medium used in the present embodiment is not particularly limited as long as it satisfies such conditions and can uniformly disperse the compound of formula (I). Specific examples include isobornylcyclohexanol represented by chemical formula (III).

 

 

Isobornylcyclohexanol represented by the chemical formula (III) does not need to be easily dispersed (vaporized) and degreased when heated, and can maintain the shape of the passivation layer forming composition after printing or coating. High boiling point material with viscosity.

Isobornyl cyclohexanol is commercially available as “Telsolve MTPH” (Nippon Terpene Chemical Co., Ltd., trade name). Isobornylcyclohexanol has a high boiling point of 308 ° C to 318 ° C, and when it is removed from the composition layer, it does not need to be degreased by heat treatment (firing) like a resin, but is scattered (vaporized) by heating. Can be eliminated. For this reason, most of the isobornylcyclohexanol contained in the composition for forming a passivation layer is dried in a drying step after applying the composition for forming a passivation layer produced by the manufacturing method of the present embodiment on a semiconductor substrate. Can be removed.

The content of the liquid medium in the composition for forming a passivation layer produced by the production method of the present embodiment is preferably 3% by mass to 95% by mass in the total mass of the composition for forming a passivation layer. It is more preferably from 90% by mass, and further preferably from 7% by mass to 80% by mass.

(Organic solvent)
Moreover, the composition for forming a passivation layer produced by the production method of the present embodiment may contain an organic solvent. Since the composition for forming a passivation layer contains an organic solvent, the adjustment of the viscosity becomes easier, the applicability of the composition for forming a passivation layer to a semiconductor substrate is further improved, and a more uniform passivation layer is formed. can do.
It does not restrict | limit especially as an organic solvent, It can select suitably as needed. Among these, an organic solvent that can dissolve the compound of formula (I) and an organoaluminum compound added as necessary to give a uniform solution is preferable, and more preferably includes at least one organic solvent.
In this embodiment, the organic solvent means an organic substance having a shear viscosity at 25.0 ° C. of less than 0.1 Pa · s. The shear viscosity of the organic solvent is a value measured in the same manner as the shear viscosity of the liquid medium.

Specific examples of organic solvents include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-i-propyl ketone, methyl-n-butyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, and methyl-n-hexyl. Ketone solvents such as ketone, diethyl ketone, di-n-propyl ketone, di-butyl ketone, trimethylnonanone, cyclohexanone, cyclopentanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, diethyl ether, methyl ethyl ether Methyl-n-propyl ether, dii-propyl ether, tetrahydrofuran, methyltetrahydrofuran, dioxane, dimethyldioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethyl Glycol di-n-propyl ether, ethylene glycol di n-butyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol methyl n-propyl ether, diethylene glycol methyl n-butyl ether, diethylene glycol di-n-propyl ether , Diethylene glycol di-n-butyl ether, diethylene glycol methyl-n-hexyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol methyl ethyl ether, triethylene glycol methyl n-butyl ether, triethylene glycol di-n- Butyl ether, triethyl Glycol methyl-n-hexyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol methyl ethyl ether, tetraethylene glycol methyl n-butyl ether, tetraethylene glycol di-n-butyl ether, tetraethylene glycol methyl-n -Hexyl ether, tetraethylene glycol di-n-butyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol di-n-propyl ether, propylene glycol di-n-butyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, Dipropylene glycol methyl ethyl ether, dip Lopylene glycol methyl-n-butyl ether, dipropylene glycol di-n-propyl ether, dipropylene glycol di-n-butyl ether, dipropylene glycol methyl-n-hexyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, tripropylene Glycol methyl ethyl ether, tripropylene glycol methyl-n-butyl ether, tripropylene glycol di-n-butyl ether, tripropylene glycol methyl-n-hexyl ether, tetrapropylene glycol dimethyl ether, tetrapropylene glycol diethyl ether, tetrapropylene glycol methyl ethyl ether Tetrapropylene glycol methyl-n-butyl ether, Ether solvents such as trapropylene glycol di-n-butyl ether and tetrapropylene glycol methyl-n-hexyl ether, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, acetic acid sec-butyl, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, 2- (2-butoxyethoxy) ethyl acetate, benzyl acetate, cyclohexyl acetate Methyl cyclohexyl acetate, nonyl acetate, methyl acetoacetate, ethyl acetoacetate, diethylene glycol methyl ether acetate, diethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, dipropylene glycol acetate Ether, glycol acetate, methoxytriethylene glycol acetate, i-amyl acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate , N-butyl lactate, n-amyl lactate, ethylene glycol methyl ether propionate, ethylene glycol ethyl ether propionate, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate , Ester solvents such as propylene glycol propyl ether acetate, γ-butyrolactone, γ-valerolactone, acetonitrile, N-methylpyrrolidinone N-ethylpyrrolidinone, Nn-propylpyrrolidinone, Nn-butylpyrrolidinone, Nn-hexylpyrrolidinone, N-cyclohexylpyrrolidinone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, etc. Protic polar solvent, methylene chloride, chloroform, dichloroethane, benzene, toluene, xylene, hexane, octane, ethylbenzene, 2-ethylhexanoic acid and other hydrophobic organic solvents, methanol, ethanol, n-propanol, i-propanol, n- Butanol, i-butanol, sec-butanol, t-butanol, n-pentanol, i-pentanol, 2-methylbutanol, sec-pentanol, t-pentanol, 3-methoxybutanol, n-hexanol 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, n-octanol, 2-ethylhexanol, sec-octanol, n-nonyl alcohol, n-decanol, sec-undecyl alcohol, trimethylnonyl Alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, cyclohexanol, methylcyclohexanol, benzyl alcohol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol , Alcohol solvents such as tripropylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol Monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol mono-n-hexyl ether, ethoxytriglycol, tetraethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl Examples thereof include glycol monoether solvents such as ether, dipropylene glycol monoethyl ether, and tripropylene glycol monomethyl ether, and terpene solvents such as terpinene, terpineol, myrcene, alloocimene, limonene, dipentene, pinene, carvone, osymene, and ferrandrene. These organic solvents are used alone or in combination of two or more.

Among them, the organic solvent preferably contains at least one selected from the group consisting of a terpene solvent, an ester solvent and an alcohol solvent from the viewpoints of imparting the passivation layer forming composition to the semiconductor substrate and patterning properties. More preferably, it contains at least one selected from the group consisting of solvents.

When the composition for forming a passivation layer contains an organic solvent, the content of the organic solvent is determined in consideration of the impartability of the composition for forming a passivation layer to a semiconductor substrate, pattern formability, and storage stability. For example, the content of the organic solvent is preferably 5% by mass to 98% by mass and more preferably 10% by mass to 95% by mass in the total mass of the composition for forming a passivation layer.

(resin)
The composition for forming a passivation layer produced by the production method of the present embodiment may further contain at least one resin. By including the resin, the shape stability of the composition layer formed by applying the composition for forming a passivation layer on a semiconductor substrate is further improved, and the passivation layer is formed in the region where the composition layer is formed. It can be formed in a desired shape.

The type of resin is not particularly limited. The resin is preferably a resin whose viscosity can be adjusted within a range in which a good pattern can be formed when the composition for forming a passivation layer is applied onto a semiconductor substrate. Specific examples of the resin include polyvinyl alcohol, polyacrylamide, polyacrylamide derivatives, polyvinylamide, polyvinylamide derivatives, polyvinylpyrrolidone, polyethylene oxide, polyethylene oxide derivatives, polysulfonic acid, polyacrylamide alkylsulfonic acid, cellulose, and cellulose derivatives (carboxymethylcellulose). , Cellulose ethers such as hydroxyethyl cellulose and ethyl cellulose), gelatin, gelatin derivatives, starch, starch derivatives, sodium alginate, sodium alginate derivatives, xanthan, xanthan derivatives, guar gum, guar gum derivatives, scleroglucan, scleroglucan derivatives, tragacanth, Tragacanth derivative, dextrin, dextrin derivative, (meta) Examples include crylic acid resin, (meth) acrylic acid ester resin (alkyl (meth) acrylate resin, dimethylaminoethyl (meth) acrylate resin, etc.), butadiene resin, styrene resin, siloxane resin, and copolymers thereof. . These resins are used singly or in combination of two or more.
In the present embodiment, (meth) acryl represents acryl or methacryl, and (meth) acrylate represents acrylate or methacrylate.

Among these resins, from the viewpoint of storage stability and pattern formation, it is preferable to use a neutral resin having no acidic or basic functional group, and even when the content is small, viscosity and From the viewpoint of adjusting the thixotropy, it is more preferable to use a cellulose derivative.
Further, the molecular weight of these resins is not particularly limited, and it is preferable to adjust appropriately in view of the desired viscosity as the composition for forming a passivation layer. The weight average molecular weight of the resin is preferably 1,000 to 10,000,000, and more preferably 1,000 to 5,000,000, from the viewpoint of storage stability and pattern formation. In addition, the weight average molecular weight of resin is calculated | required by converting using the analytical curve of a standard polystyrene from the molecular weight distribution measured using GPC (gel permeation chromatography).

When the composition for forming a passivation layer contains a resin, the content of the resin in the composition for forming a passivation layer can be appropriately selected as necessary. For example, the resin content is preferably 0.1% by mass to 50% by mass in the total mass of the composition for forming a passivation layer. From the viewpoint of expressing thixotropy that facilitates pattern formation, the resin content is more preferably 0.2% by mass to 25% by mass, and more preferably 0.5% by mass to 20% by mass. Is more preferable, and 0.5 to 15% by mass is particularly preferable.

(water)
In the first production method, in step (2), the mixed composition and water are mixed to produce a water-containing composition. In the second production method, in step (3), the liquid medium and water are mixed to create a hydrous liquid medium.
The water state may be solid or liquid. From the viewpoint of miscibility with the mixed composition, water is preferably a liquid.
In the step (2), the addition ratio of water to the mixed composition is 50 mol% to 2000 mol when the total of the compound of formula (I) and the organoaluminum compound used as necessary is 100 mol%. It is preferably mol%, more preferably 100 mol% to 1800 mol%, and still more preferably 150 mol% to 1500 mol%.
In the step (3), the addition rate of water to the liquid medium is 50 mol% to 2000 mol when the total of the compound of formula (I) and the organoaluminum compound used as necessary is 100 mol%. %, More preferably from 100 mol% to 1800 mol%, and even more preferably from 150 mol% to 1500 mol%.

(Other ingredients)
In addition to the components described above, the composition for forming a passivation layer produced by the production method of the present embodiment can further contain other components that are usually used in the field as necessary.
Examples of other components include plasticizers, dispersants, surfactants, thixotropic agents, other metal alkoxide compounds other than the compound of formula (I), and high-boiling materials. Among these, at least one selected from thixotropic agents may be included. By including at least one selected from thixotropic agents, the shape stability of the composition layer formed by applying the composition for forming a passivation layer on a semiconductor substrate is further improved, and the passivation layer is formed from the composition. It can be formed in a desired shape in the region where the layer is formed. However, the content of the thixotropic agent is preferably 5% by mass or less, more preferably 3% by mass or less, and it is preferably used within a range that does not affect the present invention.

Examples of the thixotropic agent include fatty acid amides, polyalkylene glycol compounds, organic fillers, and inorganic fillers. Examples of the polyalkylene glycol compound include compounds represented by the following general formula (IV).

R ⁶ — (O—R ⁸ ) _n —O—R ⁷ (IV)

In general formula (IV), R ⁶ and R ⁷ each independently represent a hydrogen atom or an alkyl group, and R ⁸ represents an alkylene group. n is an arbitrary integer of 3 or more. Incidentally, R ⁸ in the presence of a plurality of (O-R ⁸⁾ may or may not be the same.

Examples of the fatty acid amide include compounds represented by the following general formulas (V), (VI), (VII) and (VIII).

R ⁹ CONH ₂ ... (V)
R ⁹ CONH—R ¹⁰ —NHCOR ⁹ ... (VI)
R ⁹ NHCO—R ¹⁰ —CONHR ⁹ ... (VII)
R ⁹ CONH—R ¹⁰ —N (R ¹¹ ) ₂ ... (VIII)

In the general formulas (V), (VI), (VII) and (VIII), R ⁹ and R ¹¹ each independently represents an alkyl group or alkenyl group having 1 to 30 carbon atoms, and R ¹⁰ represents 1 to 10 carbon atoms. Represents an alkylene group. R ⁹ and R ¹¹ may be the same or different.

Examples of the organic filler include acrylic resin, cellulose resin, and polystyrene resin.

Examples of the inorganic filler include particles such as silicon dioxide, aluminum hydroxide, aluminum nitride, silicon nitride, aluminum oxide, zirconium oxide, silicon carbide, and glass.

The volume average particle diameter of the organic filler or inorganic filler is preferably 0.10 μm to 50 μm.
In this embodiment, the volume average particle diameter of the filler can be measured by a laser diffraction scattering method.

Other metal alkoxide compounds include titanium alkoxide, zirconium alkoxide, silicon alkoxide and the like.

The viscosity of the composition for forming a passivation layer produced by the production method of the present embodiment is not particularly limited, and can be appropriately selected depending on the method for applying the semiconductor substrate. For example, the viscosity of the composition for forming a passivation layer may be 0.01 Pa · s to 100,000 Pa · s. Among these, from the viewpoint of pattern formability, the viscosity of the composition for forming a passivation layer is preferably 0.1 Pa · s to 10,000 Pa · s. The viscosity is measured using a rotary shear viscometer at 25 ° C. and a shear rate of 1.0 s ⁻¹ .

In addition, from the viewpoint of pattern formation, the passivation layer forming composition has a thixo ratio (η1 / η2) calculated by dividing the shear viscosity η1 at a shear rate of 0.1 s ^{−1 by} the shear viscosity η2 at a shear rate of 10 s ⁻¹ . ) Is preferably from 1.05 to 100, more preferably from 1.1 to 50. The shear viscosity is measured at a temperature of 25 ° C. using a rotary shear viscometer equipped with a cone plate (diameter 50 mm, cone angle 1 °).

On the other hand, if the passivation layer forming composition containing high-boiling material in place of the resin, from the viewpoint of pattern formability, shear viscosity η1 at a shear rate of 1.0 s ^-1 at shear viscosity η3 at a shear rate of 1000 s ^-1 divided The thixo ratio (η1 / η3) calculated as above is preferably 1.05 to 100, more preferably 1.1 to 50.

In the first production method, the mixing method used in the step (1) for preparing the mixed composition by mixing the compound of formula (I) and the liquid medium is not particularly limited, and a commonly used mixing method can be applied. it can. In the first production method, there is no particular limitation on the mixing method used in the step (2) of mixing the mixture composition and water to prepare the water-containing composition, and a commonly used mixing method can be applied. .
In the second production method, there is no particular limitation on the mixing method used in the step (3) in which a liquid medium and water are mixed to produce a water-containing liquid medium, and a commonly used mixing method can be applied. Further, in the second production method, there is no particular limitation on the mixing method used in the step (4) in which the water-containing liquid medium and the compound of formula (I) are mixed to prepare the water-containing composition, and a commonly used mixing method is applied. can do.

In addition, the kind of component contained in the composition for forming a passivation layer, and the content of each component are determined by thermal analysis such as TG / DTA, spectral analysis such as NMR and IR, and chromatographic analysis such as HPLC and GPC. Can be confirmed.

<Semiconductor substrate with passivation layer>
The semiconductor substrate with a passivation layer of the present embodiment is a heat treatment product of a composition for forming a passivation layer provided on at least a part of a semiconductor substrate and at least one surface of the semiconductor substrate, and manufactured by the manufacturing method of the present embodiment. A passivation layer. The semiconductor substrate with a passivation layer of the present embodiment has an excellent passivation effect by having a passivation layer that is a heat-treated product of the composition for forming a passivation layer.

The semiconductor substrate is not particularly limited, and can be appropriately selected from those usually used according to the purpose. Examples of the semiconductor substrate include those obtained by doping (diffusing) p-type impurities or n-type impurities into silicon, germanium, or the like. Of these, a silicon substrate is preferable. The semiconductor substrate may be a p-type semiconductor substrate or an n-type semiconductor substrate. Among these, from the viewpoint of the passivation effect, it is preferable that the surface on which the passivation layer is formed is a semiconductor substrate having a p-type layer. Even if the p-type layer on the semiconductor substrate is a p-type layer derived from the p-type semiconductor substrate, the p-type layer is formed on the n-type semiconductor substrate or the p-type semiconductor substrate as a p-type diffusion layer or a p ⁺ -type diffusion layer. It may be.

The thickness of the semiconductor substrate is not particularly limited and can be appropriately selected according to the purpose. For example, the thickness of the semiconductor substrate can be 50 μm to 1000 μm, preferably 75 μm to 750 μm.

The thickness of the passivation layer formed on the semiconductor substrate is not particularly limited and can be appropriately selected depending on the purpose. For example, the thickness is preferably 5 nm to 50 μm, more preferably 10 nm to 30 μm, and still more preferably 15 nm to 20 μm.
In addition, the average thickness of the formed passivation layer was measured by measuring the thickness at three points by an ordinary method using an interference film thickness meter (for example, Filmetrics F20 film thickness measurement system), and the arithmetic average value thereof Calculated.

The semiconductor substrate with a passivation layer of the present embodiment can be applied to a solar cell element, a light emitting diode element, or the like. For example, the solar cell element excellent in conversion efficiency can be obtained by applying to a solar cell element.

<Method for manufacturing semiconductor substrate with passivation layer>
In the method for manufacturing a semiconductor substrate with a passivation layer according to the present embodiment, the composition layer is formed by applying the passivation layer forming composition manufactured by the manufacturing method according to the present embodiment to at least a part of at least one surface of the semiconductor substrate. Forming a passivation layer by heat-treating (sintering) the composition layer. The method for manufacturing a semiconductor substrate with a passivation layer of this embodiment may further include other steps as necessary.
In the method for manufacturing a semiconductor substrate with a passivation layer of the present embodiment, a passivation layer having an excellent passivation effect is obtained by using the composition for forming a passivation layer manufactured by the manufacturing method of the present embodiment. It can be formed by a simple method.

The method for manufacturing a semiconductor substrate with a passivation layer of this embodiment preferably further includes a step of applying an alkaline aqueous solution on the semiconductor substrate before the step of forming the composition layer. That is, it is preferable to wash the surface of the semiconductor substrate with an alkaline aqueous solution before applying the composition for forming a passivation layer on the semiconductor substrate. By washing with an alkaline aqueous solution, organic substances, particles, and the like present on the surface of the semiconductor substrate can be removed, and the passivation effect is further improved. As a cleaning method using an alkaline aqueous solution, a generally known cleaning method using RCA cleaning or the like can be exemplified. For example, by immersing the semiconductor substrate in a mixed solution of ammonia water and hydrogen peroxide water and treating at 60 ° C. to 80 ° C., organic substances, particles, and the like can be removed and washed. The washing time is preferably 10 seconds to 10 minutes, and more preferably 30 seconds to 5 minutes.

There is no particular limitation on the method for forming a composition layer by applying a passivation layer forming composition on a semiconductor substrate. For example, the method of providing the said composition for passivation layer formation on a semiconductor substrate using a well-known coating method etc. can be mentioned. Specific examples include dipping method, screen printing, ink jet method, dispenser method, spin coating method, brush coating, spray method, doctor blade method, roll coating method and the like. Among these, from the viewpoint of pattern formability and productivity, a screen printing method, an inkjet method, and the like are preferable.

The application amount of the composition for forming a passivation layer can be appropriately selected according to the purpose. For example, the thickness of the passivation layer to be formed can be appropriately adjusted so as to be a desired thickness described later.

A passivation layer is formed on a semiconductor substrate by heat-treating (baking) the composition layer formed by the composition for forming a passivation layer to form a heat-treated material layer (fired material layer) derived from the composition layer. can do.
The heat treatment (firing) conditions of the composition layer are the compound (I) contained in the composition layer and, if necessary, the organoaluminum compound, a metal oxide or composite oxide that is the heat treated product (firing product). The method is not particularly limited as long as it can be converted into a method. In order to effectively give a fixed charge to the passivation layer and obtain a more excellent passivation effect, specifically, the heat treatment (firing) temperature is preferably 300 ° C. to 900 ° C., more preferably 450 ° C. to 800 ° C. The heat treatment (firing) time can be appropriately selected according to the heat treatment (firing) temperature and the like. For example, it can be 0.1 to 10 hours, and preferably 0.2 to 5 hours.

The manufacturing method of the semiconductor substrate with a passivation layer according to the present embodiment is obtained by applying the passivation layer forming composition to the semiconductor substrate and then forming the passivation layer by a heat treatment (firing) before the step of forming the passivation layer. You may have further the process of drying-processing the composition layer which becomes. By having the process of drying the composition layer, a passivation layer having a more uniform passivation effect can be formed.

The step of drying the composition layer is not particularly limited as long as at least a part of the water and the liquid medium contained in the composition for forming a passivation layer can be removed. The drying treatment can be, for example, a heat treatment at 30 ° C. to 250 ° C. for 1 minute to 60 minutes, and is preferably a heat treatment at 40 ° C. to 220 ° C. for 3 minutes to 40 minutes. The drying treatment may be performed under normal pressure or under reduced pressure.

In the case where the composition for forming a passivation layer contains a resin, the method for manufacturing a semiconductor substrate with a passivation layer according to the present embodiment is applied before the step of forming the passivation layer by heat treatment (firing) after applying the composition for forming a passivation layer. Furthermore, you may further have the process of degreasing the composition layer which consists of a composition for formation of a passivation layer. By having a step of degreasing the composition layer, a passivation layer having a more uniform passivation effect can be formed.

The step of degreasing the composition layer is not particularly limited as long as at least part of the resin that may be contained in the composition for forming a passivation layer can be removed. The degreasing treatment can be, for example, a heat treatment at 250 ° C. to 450 ° C. for 3 minutes to 120 minutes, preferably a heat treatment at 300 ° C. to 400 ° C. for 3 minutes to 60 minutes. The degreasing treatment is preferably performed in the presence of oxygen, and more preferably performed in the air.

<Solar cell element>
The solar cell element of the present embodiment is provided on at least a part of at least a part of at least one surface of a semiconductor substrate having a pn junction formed by pn junction of a p-type layer and an n-type layer, and the passivation layer A passivation layer, which is a heat-treated product of the forming composition, and an electrode disposed on at least one of the p-type layer and the n-type layer. The solar cell element may further include other components as necessary.
The solar cell element of this embodiment is excellent in conversion efficiency by having the passivation layer formed from the composition for formation of the passivation layer manufactured by the manufacturing method of this embodiment.

The semiconductor substrate to which the composition for forming a passivation layer is applied is not particularly limited, and can be appropriately selected from those usually used according to the purpose. As the semiconductor substrate, those described in the section of the semiconductor substrate with a passivation layer of the present embodiment can be used, and those that can be suitably used are also the same. The surface of the semiconductor substrate provided with the passivation layer is preferably the back surface of the solar cell element.

The thickness of the passivation layer provided on the semiconductor substrate is not particularly limited and can be appropriately selected according to the purpose. For example, the average thickness of the passivation layer is preferably 5 nm to 50 μm, more preferably 10 nm to 30 μm, and still more preferably 15 nm to 20 μm.
There is no restriction | limiting in the shape and magnitude | size of the solar cell element of this embodiment. For example, it is preferable that one side is a substantially square having a size of 125 mm to 156 mm.

<Method for producing solar cell element>
The manufacturing method of the solar cell element of this embodiment is manufactured by the manufacturing method of this embodiment on at least a part of at least one surface of a semiconductor substrate having a pn junction part in which a p-type layer and an n-type layer are pn-junctioned. A step of forming a composition layer by applying a composition for forming a passivation layer, a step of heat-treating (firing) the composition layer to form a passivation layer, and a step of forming the p-type layer and the n-type layer. Forming an electrode on at least one of the layers. The method for manufacturing the solar cell element may further include other steps as necessary.

In the manufacturing method of the solar cell element of this embodiment, the solar cell element excellent in conversion efficiency can be manufactured by a simple method by using the composition for forming a passivation layer manufactured by the manufacturing method of this embodiment. .

As a method for disposing the electrode on at least one of the p-type layer and the n-type layer in the semiconductor substrate, a commonly used method can be employed. For example, an electrode can be manufactured by applying a paste for forming an electrode such as a silver paste or an aluminum paste to a desired region of a semiconductor substrate and performing a heat treatment (firing) as necessary.

The surface of the semiconductor substrate on which the passivation layer is provided may be a p-type layer or an n-type layer. Among these, a p-type layer is preferable from the viewpoint of conversion efficiency.
The details of the method for forming a passivation layer using the composition for forming a passivation layer are the same as the method for manufacturing a semiconductor substrate with a passivation layer described above, and the preferred embodiments are also the same.

Next, this embodiment will be described with reference to the drawings.
In addition, the magnitude | size of the member in each figure is notional, The relative relationship of the magnitude | size between members is not limited to this. Moreover, the same code | symbol is provided to the member which has the substantially same function through all the drawings, and the overlapping description may be abbreviate | omitted.
FIG. 1 is a cross-sectional view schematically showing an example of a method for producing a solar cell element having a passivation layer according to the present embodiment. However, this process diagram does not limit the present invention at all.

In FIG. 1 (1), the p-type semiconductor substrate 1 is washed with an alkaline aqueous solution to remove organic substances, particles and the like on the surface of the p-type semiconductor substrate 1. Thereby, the passivation effect improves more. As a cleaning method using an alkaline aqueous solution, a method using generally known RCA cleaning and the like can be mentioned.

Thereafter, as shown in FIG. 1 (2), the surface of the p-type semiconductor substrate 1 is subjected to alkali etching or the like to form irregularities (also referred to as texture) on the surface. Thereby, reflection of sunlight can be suppressed on the light receiving surface side. For alkali etching, an etching solution composed of NaOH and IPA (i-propanol) can be used.

Next, as shown in FIG. 1 (3), by thermally diffusing phosphorus or the like on the surface of the p-type semiconductor substrate 1, an n ⁺ -type diffusion layer 2 is formed with a thickness on the order of submicrons, and p A pn junction is formed at the boundary with the mold bulk portion.

As a method for diffusing phosphorus, for example, a method of performing several tens of minutes at 800 ° C. to 1000 ° C. in a mixed gas atmosphere of phosphorus oxychloride (POCl ₃ ), nitrogen, and oxygen can be cited. In this method, since phosphorus is diffused using a mixed gas, the n ⁺ -type diffusion layer 2 is formed not only on the light receiving surface (front surface) but also on the back surface and side surfaces (not shown) as shown in FIG. Is formed. A PSG (phosphosilicate glass) layer 3 is formed on the n ⁺ -type diffusion layer 2. Therefore, side etching is performed to remove the side PSG layer 3 and the n ⁺ -type diffusion layer 2.

Thereafter, as shown in FIG. 1 (4), the PSG layer 3 on the light receiving surface and the back surface is removed using an etching solution such as hydrofluoric acid. Further, as shown in FIG. 1 (5), the back surface is separately etched to remove the n ⁺ -type diffusion layer 2 on the back surface.

Then, as shown in FIG. 1 (6), an antireflection film 4 made of silicon nitride or the like is provided on the n ⁺ type diffusion layer 2 on the light receiving surface by a PECVD (Plasma Enhanced Chemical Vapor Deposition) method or the like with a thickness of about 90 nm. .

Next, as shown in FIG. 1 (7), a passivation layer forming composition produced by the production method of the present embodiment is applied to a part of the back surface by screen printing or the like, and after drying, a temperature of 300 ° C. to 900 ° C. Heat treatment (baking) is performed at a temperature to form the passivation layer 5.

In FIG. 5, an example of the formation pattern of the passivation layer in the back surface is shown as a schematic plan view. FIG. 7 is an enlarged schematic plan view of a portion A in FIG. FIG. 8 is an enlarged schematic plan view of a portion B in FIG. In the case of the passivation layer formation pattern shown in FIG. 5, as can be seen from FIGS. 7 and 8, the back surface passivation layer 5 is formed in a dot shape except for the portion where the back surface output extraction electrode 7 is formed in a later step. The pattern semiconductor substrate 1 is formed with an exposed pattern. The pattern of the dot-shaped openings is defined by the dot diameter (L _a ) and the dot interval (L _b ), and is preferably arranged regularly. The dot diameter (L _a ) and the dot interval (L _b ) can be arbitrarily set, but from the viewpoint of the passivation effect and the suppression of recombination of minority carriers, L _a is 5 μm to 2 mm and L _b is 10 μm to 3 mm More preferably, L _a is 10 μm to 1.5 mm and L _b is 20 μm to 2.5 mm, more preferably L _a is 20 μm to 1.3 mm and L _b is 30 μm to 2 mm.

In the case where the composition for forming a passivation layer has an excellent pattern forming property, the dot diameter (L _a ) and the dot interval (L _b ) are more regularly arranged in this dot-like opening pattern. This makes it possible to form a more preferable dot-shaped opening pattern effective for suppressing recombination of minority carriers, thereby improving the power generation efficiency of the solar cell element.

Here, a passivation layer having a desired shape is formed by applying the passivation layer forming composition to a portion where the passivation layer is to be formed (portion other than the dot-shaped opening) and heat-treating (sintering). . On the other hand, the passivation layer forming composition can be applied to the entire surface including the dot-shaped opening, and the passivation layer in the dot-shaped opening can be selectively removed by laser, photolithography, etc. after heat treatment (firing). . Alternatively, the passivation layer forming composition can be selectively applied by previously masking a portion such as a dot-shaped opening where the passivation layer forming composition is not desired to be applied with a mask material.

Next, as shown in FIG. 1 (8), a silver electrode paste containing glass particles for forming the light receiving surface collecting electrode 8 and the light receiving surface output extraction electrode 9 is applied to the light receiving surface by screen printing or the like. FIG. 4 is a schematic plan view showing an example of the light receiving surface of the solar cell element. As shown in FIG. 4, the light receiving surface electrode includes a light receiving surface current collecting electrode 8 and a light receiving surface output extraction electrode 9. In order to secure a light receiving area, it is necessary to suppress the formation area of these light receiving surface electrodes. In addition, from the viewpoint of resistivity and productivity of the light receiving surface electrode, the width of the light receiving surface current collecting electrode 8 is preferably 10 μm to 250 μm, and the width of the light receiving surface output extraction electrode 9 is preferably 100 μm to 2 mm. In FIG. 4, two light receiving surface output extraction electrodes 9 are provided. However, from the viewpoint of minority carrier extraction efficiency (power generation efficiency), the number of light receiving surface output extraction electrodes 9 may be three or four. it can.

On the other hand, as shown in FIG. 1 (8), an aluminum electrode paste containing glass powder forming the back surface collecting aluminum electrode 6 and a silver electrode paste containing glass particles forming the back surface output extraction electrode 7 are formed on the back surface. Apply by screen printing. FIG. 9 is a schematic plan view showing an example of the back surface of the solar cell element. The width of the back surface output extraction electrode 7 is not particularly limited, but the width of the back surface output extraction electrode 7 is preferably 100 μm to 10 mm from the viewpoint of the connectivity of the wiring material in the subsequent manufacturing process of the solar cell.

After applying the electrode paste to the light-receiving surface and the back surface, after drying, heat-treat (fire) both the light-receiving surface and the back surface at a temperature of about 450 ° C to 900 ° C in the air, and collect the electrode on the light-receiving surface. 8 and the light receiving surface output extraction electrode 9, and the back surface collecting aluminum electrode 6 and the back surface output extraction electrode 7 are formed on the back surface, respectively.

After heat treatment (firing), as shown in FIG. 1 (9), on the light receiving surface, the glass particles contained in the silver electrode paste forming the light receiving surface electrode react with the antireflection film 4 (fire through), The light-receiving surface electrode (light-receiving surface current collecting electrode 8, light-receiving surface output extraction electrode 9) and the n ⁺ -type diffusion layer 2 are electrically connected (ohmic contact). On the other hand, on the back surface, in the portion where the semiconductor substrate 1 is exposed in the form of dots (the portion where the passivation layer 5 is not formed), the aluminum in the aluminum electrode paste diffuses into the semiconductor substrate 1 by heat treatment (firing). , P ⁺ -type diffusion layer 10 is formed. In the present embodiment, by using the passivation layer forming composition produced by the production method of the present embodiment, which is excellent in pattern formability, a passivation layer excellent in the passivation effect can be formed by a simple method, and the power generation performance is excellent. A solar cell element can be manufactured.

FIG. 2 is a cross-sectional view schematically showing another example of a method for manufacturing a solar cell element having a passivation layer according to the present embodiment, and the n ⁺ -type diffusion layer 2 on the back surface is etched. A solar cell element can be manufactured in the same manner as in FIG. 1 except that the back surface is further planarized after being removed by the treatment. When flattening, a technique such as immersing the back surface of the semiconductor substrate in a mixed solution of nitric acid, hydrofluoric acid and acetic acid or a potassium hydroxide solution can be used.

FIG. 3: shows process drawing which shows typically another example of the manufacturing method of the solar cell element which has a passivation layer which concerns on this embodiment as sectional drawing. This method is the same as the method shown in FIG. 1 until the step of forming the texture structure, the n ⁺ -type diffusion layer 2 and the antireflection film 4 on the semiconductor substrate 1 (FIGS. 19 (19) to (24)).

After forming the antireflection film 4, as shown in FIG. 3 (25), a composition for forming a passivation layer is applied. FIG. 6 shows a schematic plan view of another example of the formation pattern of the passivation layer on the back surface. In the formation pattern of the passivation layer shown in FIG. 6, dot-like openings are arranged on the entire back surface, and dot-like openings are also arranged on the portion where the back-surface output extraction electrode is formed in a later step.

Thereafter, as shown in FIG. 3 (26), from the portion where the semiconductor substrate 1 in a dot shape is exposed (the portion passivation layer 5 is not formed) on the rear surface, to diffuse boron or aluminum, p ⁺ -type diffusion layer 10 Form. When boron is diffused when forming the p ⁺ -type diffusion layer 10, a method of treating at a temperature around 1000 ° C. in a gas containing boron trichloride (BCl ₃ ) can be used. However, since the method of gas diffusion is the same as in the case of using phosphorus oxychloride, the p ⁺ -type diffusion layer 10 is formed on the light receiving surface, the back surface, and the side surface of the substrate. It is necessary to take measures such as masking the portions other than the openings to prevent boron from diffusing into unnecessary portions of the p-type semiconductor substrate 1.

Further, when aluminum is diffused when forming the p ⁺ -type diffusion layer 10, the aluminum paste is applied to the dot-shaped opening, and this is heat-treated (fired) at a temperature of 450 ° C. to 900 ° C. It is possible to use a technique in which aluminum is diffused from the opening to form the p ⁺ -type diffusion layer 10 and then a heat treatment product layer (baked product layer) made of an aluminum paste on the p ⁺ -type diffusion layer 10 is etched with hydrochloric acid or the like. it can.

Next, as shown in FIG. 3 (27), the aluminum electrode 11 for backside current collection is formed by physically depositing aluminum on the entire backside.

Thereafter, as shown in FIG. 3 (28), a silver electrode paste containing glass particles forming the light receiving surface collecting electrode 8 and the light receiving surface output extraction electrode 9 is applied to the light receiving surface by screen printing or the like. In this case, a silver electrode paste containing glass particles for forming the back surface output extraction electrode 7 is applied by screen printing or the like. The silver electrode paste on the light receiving surface is applied in a pattern according to the shape of the light receiving surface electrode shown in FIG. 4, and the silver electrode paste on the back surface is applied in a pattern according to the shape of the back electrode shown in FIG.

After applying the electrode paste to the light receiving surface and the back surface, respectively, after drying, the light receiving surface and the back surface are both heat-treated (fired) at a temperature of about 450 ° C. to 900 ° C. in air, as shown in FIG. A light receiving surface collecting electrode 8 and a light receiving surface output extraction electrode 9 are formed on the light receiving surface, and a back surface output extraction electrode 7 is formed on the back surface. At this time, the light receiving surface electrode and the n ⁺ -type diffusion layer 2 are electrically connected on the light receiving surface, and the back surface collecting aluminum electrode 11 and the back surface output extraction electrode 7 formed by vapor deposition are electrically connected on the back surface. Is done.

<Solar cell>
The solar cell of the present embodiment includes at least one of the solar cell elements of the present embodiment, and is configured by arranging a wiring material on the electrode of the solar cell element. That is, the solar cell of this embodiment has the solar cell element and a wiring material disposed on the electrode of the solar cell element.
The solar cell of the present embodiment is further configured by connecting a plurality of solar cell elements via a wiring material and further sealing with a sealing material as necessary. The wiring material and the sealing material are not particularly limited, and can be appropriately selected from those usually used in the technical field.

Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to these examples. Unless otherwise specified, “%” is based on mass.

<Example 1>
(Preparation of composition 1 for forming a passivation layer)
4.927 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21) and 28.536 g of isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.) Taken and kneaded. Thereto, 1.725 g of purified water was added and kneaded. A highly viscous mixture was obtained. Further, 4.927 g of aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH) and 10.833 g of terpineol (Nippon Terpene Chemical Co., Ltd.) are mixed and kneaded for 5 minutes for forming a passivation layer. Composition 1 was prepared.

(Evaluation of thixotropy)
The shear viscosity of the composition 1 for forming a passivation layer prepared above was attached to a rotary shear viscometer (AntonPaar, MCR301) with a cone plate (diameter 50 mm, cone angle 1 °) at a temperature of 25 ° C. Measurements were made under conditions of speeds of 0.1 s ^-1 and 10 s ^-1 respectively.
The shear viscosity (η1) at a shear rate of 0.1 s ⁻¹ was 252 Pa · s, and the shear viscosity (η2) at a shear rate of 10 s ⁻¹ was 21.1 Pa · s. The thixo ratio (η1 / η2) when the shear rate was 0.1 s ⁻¹ and 10 s ⁻¹ was 11.9.

(Evaluation of pattern formability)
When the pattern forming property of the composition for forming a passivation layer was evaluated, a single crystal p-type silicon substrate (50 mm square, thickness 770 μm, hereinafter simply referred to as a silicon substrate) having a mirror shape was used as a semiconductor substrate. .

In the evaluation of pattern formability, the prepared composition 1 for forming a passivation layer was printed on the entire surface of the silicon substrate except for the dot-shaped openings with the pattern shown in FIG. 8 using a screen printing method. Here, the dot-like opening pattern used in the evaluation has a dot diameter (L _a ) of 714 μm, a dot interval (L _b ) of 2.0 mm, a dot diameter (L _a ) of 535 μm, and a dot interval (L _b ). 4 mm, 1.5 mm, dot diameter (L _a ) of 357 μm, dot interval (L _b ) of 1.0 mm, dot diameter (L _a ) of 178 μm, and dot interval (L _b ) of 0.5 mm were prepared.
Thereafter, the silicon substrate provided with the composition 1 for forming a passivation layer was heated at 150 ° C. for 5 minutes, and the liquid medium was scattered to perform a drying process. Next, the silicon substrate was heat-treated (baked) at a temperature of 700 ° C. for 10 minutes and then allowed to cool at room temperature (25 ° C.). The heat treatment (firing) was performed using a diffusion furnace (ACCURON CQ-1200, Hitachi Kokusai Electric Co., Ltd.) under atmospheric conditions under conditions of a maximum temperature of 700 ° C. and a holding time of 10 minutes.

In the evaluation of pattern formability, the dot diameter (L _a ) of the dot-shaped opening in the passivation layer formed on the substrate after heat treatment (firing) was measured. In addition, the dot diameter (L _a ) was measured at 10 points, and the average value was calculated.
Here, with respect to the dot diameter (L _a ) immediately after printing, the change rate of the dot diameter (L _a ) after heat treatment (firing) is less than 15% A, B is 15% or more and less than 30% B, 30% or more was evaluated as C. If evaluation is A or B, the pattern formability of the composition for forming a passivation layer is good.

(Measurement of effective lifetime)
The prepared composition 1 for forming a passivation layer was printed on the entire surface of a silicon substrate using a screen printing method. Thereafter, the silicon substrate provided with the composition 1 for forming a passivation layer was heated at 150 ° C. for 5 minutes, and the liquid medium was scattered to perform a drying process. Thereafter, printing and drying were performed on the other surface of the silicon substrate. Next, the silicon substrate was heat-treated (baked) at a temperature of 700 ° C. for 10 minutes and then allowed to cool at room temperature (25 ° C.). The heat treatment (firing) was performed using a diffusion furnace (ACCURON CQ-1200, Hitachi Kokusai Electric Co., Ltd.) under atmospheric conditions under conditions of a maximum temperature of 700 ° C. and a holding time of 10 minutes.

The effective lifetime of the evaluation substrate obtained above was measured by a reflected microwave photoconductive decay method at room temperature (25 ° C.) using a lifetime measuring device (Nippon Semi-Lab Co., Ltd., WT-2000PVN). In the obtained evaluation substrate, the effective lifetime of the region to which the composition for forming a passivation layer was applied was 1250 μs.

<Example 2>
5.177 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21), 33.985 g of isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.), 5.166 g of aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH) and 5.171 g of terpineol (Nippon Terpene Chemical Co., Ltd.) were weighed and kneaded. Thereto, 1.985 g of purified water was added and mixed, and kneaded for 5 minutes to prepare a composition 2 for forming a passivation layer.
Thereafter, in the same manner as in Example 1, evaluation of the thixotropy, evaluation of pattern formation, and evaluation of effective lifetime of the composition 2 for forming a passivation layer were performed.

(Production of solar cell element)
First, a single crystal p-type semiconductor substrate (125 mm square, thickness 200 μm) was prepared, and texture structures were formed on the light receiving surface and the back surface by alkali etching. Next, in a mixed gas atmosphere of phosphorus oxychloride (POCl ₃ ), nitrogen and oxygen, treatment was performed at a temperature of 900 ° C. for 20 minutes to form n ⁺ -type diffusion layers on the light receiving surface, the back surface, and the side surface. Thereafter, side etching was performed to remove the side PSG layer and the n ⁺ -type diffusion layer, and the PSG layer on the light-receiving surface and the back surface was removed using an etching solution containing hydrofluoric acid. Further, the back surface was separately etched to remove the n ⁺ -type diffusion layer on the back surface. Thereafter, an antireflection film made of silicon nitride was formed on the n ⁺ -type diffusion layer on the light receiving surface with a thickness of about 90 nm by PECVD.

Next, the passivation layer forming composition 2 prepared above was applied to the back surface in the pattern of FIGS. 5, 7 and 8, and then dried at a temperature of 150 ° C. for 5 minutes, and a diffusion furnace (ACCURON CQ-1200, The passivation layer 1 was formed by performing heat treatment (baking) under the conditions of a maximum temperature of 700 ° C. and a holding time of 10 minutes in an atmospheric atmosphere using Hitachi Kokusai Electric). 5, 7, and 8, the back surface passivation layer 1 is formed in a pattern in which the p-type semiconductor substrate is exposed in a dot shape except for a portion where the back surface output extraction electrode is formed in a later step. The pattern of the dot-shaped openings has the same shape as the smallest one used in the evaluation of pattern formability, the dot diameter (L _a ) is 178 μm, and the dot interval (L _b ) is 0.5 mm. .

Next, a commercially available silver electrode paste (PV-16A, DuPont) was printed on the light receiving surface with the pattern shown in FIG. 4 by screen printing. The electrode pattern is composed of a 120 μm wide light receiving surface current collecting electrode and a 1.5 mm wide light receiving surface output extraction electrode, and printing conditions (screen plate mesh) so that the thickness after heat treatment (firing) is 20 μm. , Printing speed and printing pressure) were appropriately adjusted. This was heated at a temperature of 150 ° C. for 5 minutes, and the liquid medium was scattered to perform a drying process.

On the other hand, a commercially available aluminum electrode paste (PVG-AD-02, PVG Solutions Co., Ltd.) and a commercially available silver electrode paste (PV-505, DuPont Co., Ltd.) are printed on the back surface in the pattern shown in FIG. did. The pattern of the back surface output extraction electrode made of silver electrode paste was constituted by 123 mm × 4 mm.

The printing conditions (screen plate mesh, printing speed and printing pressure) of the silver electrode paste and the aluminum electrode paste are set so that the thickness of the back surface output extraction electrode and the back surface collecting electrode after heat treatment (firing) is 20 μm. Adjusted accordingly.
After printing each electrode paste, it was heated for 5 minutes at a temperature of 150 ° C., and the liquid medium was scattered to perform a drying treatment.

Subsequently, heat treatment (firing) was performed using a tunnel furnace (single-line transport W / B tunnel furnace, Noritake Co., Ltd.) under atmospheric conditions at a maximum temperature of 800 ° C. and a holding time of 10 seconds. The solar cell element 1 in which the electrode was formed was produced.

On the light receiving surface output extraction electrode and the back surface output extraction electrode of the solar cell element 1 obtained above, a wiring member (solder-plated rectangular wire for solar cell, product name: SSA-TPS 0.2 × 1.5 (20 ), Sn-Ag-Cu lead-free solder plated to a maximum thickness of 20μm per side on a copper wire of thickness 0.2mm x width 1.5mm (Hitachi Metals Co., Ltd.), and a tab wire connection device ( By using NTS-150-M, Tabbing & Stringing Machine, NPC Corporation, and melting the solder under the conditions of a maximum temperature of 250 ° C. and a holding time of 10 seconds, the above wiring member, light receiving surface output extraction electrode and back surface output The extraction electrode was connected.

Then, using a glass plate (white plate tempered glass 3KWE33, Asahi Glass Co., Ltd.), a sealing material (ethylene vinyl acetate; EVA), and a back sheet, as shown in FIG. 10, glass plate 16 / sealing material 14 / wiring material 13 are connected in the order of solar cell element 12 / sealing material 14 / back sheet 15, and a part of the wiring member is laminated using a vacuum laminator (LM-50 × 50, NPC Corporation). Was laminated for 5 minutes at a temperature of 140 ° C. so as to expose the solar cell 1.

The evaluation of the power generation performance of the produced solar cell was performed using pseudo-sunlight (WXS-155S-10, Wacom Denso Co., Ltd.) and voltage-current (IV) evaluation measuring instrument (IV CURVE TRACER MP-180, This was performed in combination with a measuring device of Eihiro Seiki Co., Ltd. Jsc (short circuit current), Voc (open voltage), F. F. (Curve factor) and Eff (conversion efficiency) were measured in accordance with JIS-C-8913 (fiscal 2005) and JIS-C-8914 (fiscal 2005), respectively.

<Example 3>
4.483 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21), 36.025 g of isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.), 4.496 g of aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH) and 13.114 g of terpineol (Nippon Terpene Chemical Co., Ltd.) were weighed and kneaded. Thereto, 1.793 g of purified water was added, mixed, and kneaded for 5 minutes to prepare a composition 3 for forming a passivation layer.
Thereafter, in the same manner as in Example 1, evaluation of the thixotropy, evaluation of pattern formation, and evaluation of effective lifetime of the composition 3 for forming a passivation layer were performed.

<Comparative Example 1>
5.856 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21), 35.070 g of isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.), Composition for forming a passivation layer by weighing 5.900 g of aluminum ethylacetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH) and 12.979 g of terpineol (Nippon Terpene Chemical Co., Ltd.) and kneading for 5 minutes. 4 was prepared.
Thereafter, in the same manner as in Example 1, evaluation of the thixotropy of the composition 4 for forming a passivation layer, evaluation of pattern formation, and evaluation of effective lifetime were performed. Further, in the same manner as in Example 2, the solar cell element 2 and the solar cell 2 were produced, and the power generation performance was evaluated.

<Comparative example 2>
5.170 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21) was weighed, and 2.002 g of purified water was added and mixed. A white mass formed. 28.313 g of isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.), 5.302 g of aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH), and terpineol (Nippon Terpene Chemical Co., Ltd.) 10.15 g was weighed and kneaded for 5 minutes to prepare a composition 5 for forming a non-uniform passivation layer containing a lump.
Thereafter, application by screen printing was attempted. However, since the application could not be performed, evaluation of pattern formation and evaluation of effective lifetime could not be performed. Further, since there was a mass, the shear viscosity could not be measured, and thixotropy could not be evaluated.

<Comparative Example 3>
5.042 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21) and 10.021 g of terpineol (Nippon Terpene Chemical Co., Ltd.) were weighed and mixed. . To this, 2.016 g of purified water was added and mixed. A white mass formed. 27.945 g of isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.) and 5.046 g of aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH) are mixed and kneaded for 5 minutes to form a lump. A composition 6 for forming a non-uniform passivation layer including the above was prepared.
Thereafter, application by screen printing was attempted. However, since the application could not be performed, evaluation of pattern formation and evaluation of effective lifetime could not be performed. Further, since there was a mass, the shear viscosity could not be measured, and thixotropy could not be evaluated.

<Comparative example 4>
Purified water 1.799 was added to and mixed with 4.478 g of aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH). A white mass formed. 36.183 g of isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.), 4.447 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21), 13.116 g of terpineol (Nippon Terpene Chemical Co., Ltd.) was weighed, mixed, and kneaded for 5 minutes to prepare a composition 7 for forming a non-uniform passivation layer including a solid product.
Thereafter, shear viscosity was measured and thixotropy was evaluated. Moreover, although application by screen printing was attempted, since the application could not be performed, evaluation of pattern formation and evaluation of effective lifetime could not be performed.

<Comparative Example 5>
5.485 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21), aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH) was weighed 5.490 g, isobornylcyclohexanol (Nippon Terpene Chemical Co., Ltd.) 18.574 g, and terpineol (Nippon Terpene Chemical Co., Ltd.) 6.940 g, mixed and kneaded for 5 minutes. Furthermore, 4.018 g of ethanol (Wako Pure Chemical Industries) was weighed and mixed, and kneaded for 5 minutes to prepare a passivation layer forming composition 8.
Thereafter, the thixotropy of the passivation layer forming composition 8 was evaluated in the same manner as in Example 1. Moreover, although application by screen printing was attempted, since the application could not be performed, evaluation of pattern formation and evaluation of effective lifetime could not be performed.

<Comparative Example 6>
6.864 g of pentaethoxyniobium (Hokuko Chemical Co., Ltd., structural formula: Nb (OC ₂ H ₅ ) ₅ , molecular weight: 318.21), aluminum ethyl acetoacetate diisopropylate (Kawaken Fine Chemical Co., Ltd., trade name: ALCH) was weighed and mixed for 5 minutes by weighing 6.857 g, isobornylcyclohexanol (Nihon Terpene Chemical Co., Ltd.) 23.220 g, and terpineol (Nihon Terpene Chemical Co., Ltd.) 8.676 g. Further, 8.926 g of i-propanol (Wako Pure Chemical Industries, Ltd.) was weighed and mixed and kneaded for 5 minutes to prepare a passivation layer forming composition 9.
Thereafter, the thixotropy of the passivation layer forming composition 9 was evaluated in the same manner as in Example 1. Moreover, although application by screen printing was attempted, since the application could not be performed, evaluation of pattern formation and evaluation of effective lifetime could not be performed.

Table 1 summarizes the components used in each step in each example and comparative example. In Table 1, compounds (I), (II) and (III) are each a compound represented by general formula (I), a compound represented by general formula (II) and a compound represented by general formula (III). Represents. EtOH and IPA represent ethanol and i-propanol, respectively. “-” Indicates that the corresponding process was not performed.

 

 

In Table 2, the formula (I), the formula (II) and the formula (III) are respectively represented by the compound represented by the general formula (I), the compound represented by the general formula (II) and the general formula (III). Represents a compound.

Table 3 summarizes the measurement results of shear viscosity, pattern formability, and effective lifetime measurement results in each example and comparative example. In the table, “-” indicates that the corresponding item was not evaluated.

Table 4 summarizes the evaluation results of the solar cells produced in Example 2 and Comparative Example 1.

The disclosure of Japanese Patent Application No. 2014-138950 filed on July 4, 2014 is incorporated herein by reference in its entirety. In addition, all the documents, patent applications, and technical standards described in this specification are the same as when individual documents, patent applications, and technical standards are specifically and individually described to be incorporated by reference. Which is incorporated herein by reference.

Claims (12)

The manufacturing method of the composition for formation of a passivation layer including the process of following (1) and following (2).
(1) A step of mixing a compound represented by the following general formula (I) and a liquid medium to produce a mixed composition.
(2) A step of mixing the mixed composition and water to produce a water-containing composition.
M (OR ¹ ) _m (I)
[In General Formula (I), M represents at least one selected from the group consisting of Al, Nb, Ta, VO, Y, and Hf. R ¹ independently represents an alkyl group or an aryl group. m represents an integer of 1 to 5. ] The compound represented by the following general formula (II) is mixed with the liquid medium and the compound represented by the general formula (I) in the step (1), or after the step (2). The method for producing a composition for forming a passivation layer according to claim 1, which is mixed with the water-containing composition.

[In General Formula (II), each R ² independently represents an alkyl group. n represents an integer of 1 to 3. X ² and X ³ each independently represent an oxygen atom or a methylene group. R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group. ] The manufacturing method of the composition for formation of a passivation layer including the process of following (3) and following (4).
(3) A step of preparing a water-containing liquid medium by mixing a liquid medium and water.
(4) A step of preparing a water-containing composition by mixing the water-containing liquid medium and a compound represented by the following general formula (I).
M (OR ¹ ) _m (I)
[In General Formula (I), M represents at least one selected from the group consisting of Al, Nb, Ta, VO, Y, and Hf. R ¹ independently represents an alkyl group or an aryl group. m represents an integer of 1 to 5. ] The compound represented by the following general formula (II) is mixed with the compound represented by the general formula (I) and the water-containing liquid medium in the step (4), or in the step (4). The method for producing a composition for forming a passivation layer according to claim 3, which is mixed with the water-containing composition later.

[In General Formula (II), each R ² independently represents an alkyl group. n represents an integer of 1 to 3. X ² and X ³ each independently represent an oxygen atom or a methylene group. R ³ , R ⁴ and R ⁵ each independently represents a hydrogen atom or an alkyl group. ] The method for producing a composition for forming a passivation layer according to claim 1 or 2, wherein the mixed composition has a shear viscosity of 0.1 Pa · s or more under conditions of 25.0 ° C and a shear rate of 10 s ^-1. . The method for producing a composition for forming a passivation layer according to any one of claims 1 to 5, wherein the liquid medium contains a compound represented by the following general formula (III).

When the total amount of the compound represented by the general formula (I) and the compound represented by the general formula (II) used as necessary is 100 mol%, the water addition rate is 50 mol% to 2000 mol. The method for producing a composition for forming a passivation layer according to any one of claims 1 to 6, wherein the composition is mol%. A semiconductor substrate;
A passivation layer which is provided on at least a part of at least one surface of the semiconductor substrate and is a heat-treated product of the passivation layer forming composition manufactured by the manufacturing method according to any one of claims 1 to 7. When,
A semiconductor substrate with a passivation layer. A composition layer is formed by applying a composition for forming a passivation layer produced by the production method according to any one of claims 1 to 7 to at least a part of at least one surface of a semiconductor substrate. Process,
Heat-treating the composition layer to form a passivation layer;
The manufacturing method of the semiconductor substrate with a passivation layer which has this. a semiconductor substrate having a pn junction formed by p-type junction of a p-type layer and an n-type layer;
A passivation layer which is provided on at least a part of at least one surface of the semiconductor substrate and is a heat-treated product of the passivation layer forming composition manufactured by the manufacturing method according to any one of claims 1 to 7. When,
An electrode disposed on at least one of the p-type layer and the n-type layer;
A solar cell element having The manufacturing method according to any one of claims 1 to 7, wherein at least part of at least one surface of a semiconductor substrate having a pn junction formed by pn junction of a p-type layer and an n-type layer is manufactured. Providing a composition for forming a passivation layer to form a composition layer; and
Heat-treating the composition layer to form a passivation layer;
Disposing an electrode on at least one of the p-type layer and the n-type layer;
The manufacturing method of the solar cell element which has this. The solar cell element according to claim 10,
A wiring material disposed on the electrode of the solar cell element;
A solar cell having:

Images