KR20120077710A - Bifacial photovoltaic localized emitter solar cell and method for manufacturing thereof - Google Patents

Abstract

The present invention forms a light-receiving portion on the front and rear surfaces of the substrate, locally emitters and electrodes are formed on the front light-receiving portion of the substrate, and a base and electrode are formed on the rear light-receiving portion of the substrate. A solar cell and a method for manufacturing the same, comprising a first conductive substrate having a front electrode and a rear electrode on upper and lower surfaces thereof, wherein a high concentration doped region of a second conductive impurity is locally formed in an upper layer of the substrate. The front electrode is formed in contact with the high concentration doped region of the second conductive impurity, a high concentration doped region of the first conductive impurity is locally formed in the lower layer of the substrate, and the back electrode is formed of the first conductive type. It is characterized by being formed in contact with the highly doped region of the impurities, thereby increasing the light receiving portion of the substrate to absorb even the sunlight reflected from the ground surface W can increase the sunlight absorption, whereby it is capable of maximizing the efficiency of the solar cell effect.

Description

Bilateral Photovoltaic Localized Emitter Solar Cell and Method for Manufacturing Thereof}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided light receiving type localized emitter solar cell and a method for manufacturing the same, and more particularly, to a double-sided light receiving type localized emitter solar cell in which an electrode is formed locally at a light receiving portion of a substrate.

The solar cell is a key element of photovoltaic power generation that converts sunlight directly into electricity, and is basically a diode composed of a p-n junction.

In the process of converting sunlight into electricity by solar cells, solar light is incident on the solar cells to generate electron-hole pairs inside the solar cells, and electrons move to n layers and holes move to p layers by the electric field. Thus, photovoltaic power is generated between the pn junctions, and when a load or a system is connected to both ends of the solar cell, current flows to generate power.

On the other hand, solar cells are classified into various types according to the shape of the light absorption layer or the impurity ions, which are pn junction layers. Examples of the light absorption layer include silicon (Si). The silicon substrate type used as the light absorption layer is divided into a thin film type which forms a light absorption layer by depositing silicon in a thin film form.

Looking at the general structure of the silicon substrate type of silicon-based solar cell as an example.

As shown in FIG. 1, the second conductive semiconductor layer 12, which is an emitter layer, is stacked on the first conductive semiconductor layer 11, which is a base layer, and on the upper surface of the second conductive semiconductor layer 12. A front electrode 14 having a pattern such as a finger bar or a bus bar is formed and a rear electrode 15 is provided on a lower surface of the first conductive semiconductor layer 11.

In this case, the first conductive semiconductor layer 11 and the second conductive semiconductor layer 12 are implemented on one silicon substrate 10, and the lower portion of the silicon substrate 10 is the first conductive semiconductor layer 11. The upper portion of the silicon substrate 10 is divided into the second conductive semiconductor layer 12, and a lower concentration doped region of the first conductive impurity for forming a backside electric field is formed below the first conductive semiconductor layer 11. The second conductive semiconductor layer 12 having (10-1) and the front electrode 14 formed on the upper surface thereof is optionally provided with a highly doped region 10-2 of the second conductive impurity.

Here, the highly doped region 10-1 of the first conductive impurity formed entirely under the first conductive semiconductor layer 11 may have a rear electric field having a higher energy barrier than that of the first conductive semiconductor layer 11. Since it is formed, the minority transporter 1 photogenerated by solar incidence in the first conductive semiconductor layer 11 is prevented from moving to the rear electrode 15.

Looking at the general manufacturing process of such a substrate-type silicon solar cell, first preparing a silicon substrate 10 of the first conductivity type, surface texturing of the prepared silicon substrate 10, doping impurity ion (Doping) of the second conductivity type The second conductive semiconductor layer 12 may be formed through diffusion, and the front electrode 14 and the rear electrode 15 may be formed.

Meanwhile, before the front electrode 14 and the back electrode 15 are formed, impurities including impurities such as a PSG (Phosphorus Silicate Glass) film or a BSG (Boron Silicate Glass) film formed on the surface of the substrate 10 by a diffusion process are formed. A cleaning process for removing an oxide film and a process for forming an anti-reflection film 13 on the second conductive semiconductor layer 12, and the like, to reduce contact resistance between the surface of the silicon substrate 10 and the front electrode 14. In order to form the second conductive semiconductor layer 12 corresponding to the portion where the front electrode 14 is to be formed, a highly doped region 10-2, that is, an emitter, of the second conductive impurity is selectively formed.

In addition, after the formation of the front electrode 14 and the rear electrode 15, a high concentration doped region 10-1 of the first conductive type impurity is entirely formed under the first conductive semiconductor layer 11 through a firing process. And forming a trench for disconnection of a predetermined depth along the circumference of the front surface of the substrate using a laser.

When the second conductive semiconductor layer 12 is formed, the silicon substrate 10 is immersed in a solution containing the second conductive impurity ions and subsequently subjected to a heat treatment process, thereby forming the second conductive impurity ions into a silicon substrate ( 10), the second conductive semiconductor layer is formed on the side of the substrate in addition to the upper portion of the silicon substrate 10. Thus, the second conductive semiconductor layer formed on the side of the substrate is the front electrode 14; Since the back electrode 15 is shorted to act as a factor of reducing photoelectric conversion efficiency of the solar cell, the front electrode 14 and the rear surface of the second conductive semiconductor layer formed on the side of the silicon substrate 10 are reduced. This is because it is necessary to interrupt the electrical connection between the electrodes 15.

Looking at the movement of the minority transporter (1) during photovoltaic power generation in such a general solar cell, for example, when the first conductivity type is p-type, the second conductivity type is n-type, as the solar light enters the first conductive semiconductor The electrons, which are the minority carriers 1 generated in the layer 11, move toward the front surface of the silicon substrate 10 on which the second conductive semiconductor layer 12, that is, the emitter layer, is formed. At this time, the hole which is the majority carrier 2 is moved toward the rear side of the silicon substrate 10.

In such a general solar cell, the impurity doping concentration in the depth direction is highest at the top and decreases toward the bottom, and accordingly, the conduction band is lowered toward the top in the energy band structure. Since the semiconductor layer 12, that is, the emitter layer, is formed on the entire light-receiving surface of the silicon substrate 10, the minority transport photogenerated in the first conductive semiconductor layer 11 by the depth energy band structure of the emitter layer. The self moves along the emitter layer, and in particular, moves along the surface of the silicon substrate 10 above the emitter layer adjacent to the anti-reflection film 13 and is collected by the front electrode 14.

However, since the surface area of the silicon substrate 10, which is the movement path of the minority transporter 1, is a high density of defects in which a large number of crystal defects and impurities exist, the minority transporter 1 has such a conventional solar cell. There is a fear that it may be easily lost by recombination before being collected by the front electrode 14.

Furthermore, in the conventional solar cell, since the front electrode 14 having a large line width W within a range of 100 µm to 140 µm must be formed on the front surface of the silicon substrate 10, that is, the light receiving surface, it is sufficient to maintain the light receiving rate. In order to secure the light receiving surface of the area, the distance d between the front electrodes 14 is very large, within 1800 μm to 2300 μm, so that the front surface of the minority transporter 1 photogenerated in the first conductive semiconductor layer 11. Since the travel distance to the electrode 14 becomes long, there is a fear that the minority transporter 1 may be easily lost by recombination before being collected by the front electrode 14.

That is, the conventional solar cell has a problem in that the photoelectric conversion efficiency is low due to its high recombination rate of the photo-generated minority transporter 1.

In addition, in the conventional solar cell, due to its structure, a metallic back electrode 15 is formed on the rear surface of the substrate 10 as a whole, the manufacturing cost is high, and solar light reflected from the ground surface cannot be absorbed at all. have.

In addition, a conventional solar cell requires a complicated process procedure such as a cleaning process for removing an oxide film and an insulation process for forming a trench for disconnection, and thus, a manufacturing period and a manufacturing cost are high.

The present invention has been made to solve the above-described problems, the light-receiving portion is formed on the front and rear surfaces of the substrate, the emitter and the electrode is formed locally on the front light-receiving portion of the substrate, local to the rear light-receiving portion of the substrate To provide a double-sided light-receiving localized emitter solar cell having a base and an electrode and a method of manufacturing the same, an object thereof.

A solar cell according to an embodiment of the present invention for achieving the above object, includes a first conductive substrate having a front electrode and a rear electrode on the upper and lower surfaces, the second conductive portion on the upper layer of the substrate A high concentration doped region of a type impurity is formed locally, the front electrode is formed in contact with the high concentration doped region of the second conductive impurity, and a high concentration doped region of a first conductive type impurity is locally formed in the lower layer of the substrate. The back electrode may be formed in contact with a high concentration doped region of the first conductive impurity.

Here, a passivation layer is formed on the upper and lower surfaces of the substrate except for the portion where the front electrode and the back electrode are formed, and an anti-reflective coating (ARC) is preferably stacked on the passivation layer. .

In addition, the front electrode and the back electrode is preferably provided with a seed layer in the lower layer in direct contact with the substrate, respectively.

In this case, the front electrode and the rear electrode is preferably formed in a pattern of a finger line shape.

Further, the front electrode is formed with a line width of 20 ㎛ to 40 ㎛, preferably formed at intervals of 450 ㎛ to 2300 ㎛.

On the other hand, the method of manufacturing a double-sided light receiving localized emitter solar cell according to an embodiment of the present invention, preparing a substrate of the first conductive type; Forming a highly doped region of a second conductive impurity locally in an upper layer of the substrate; Forming a heavily doped region of a first conductivity type impurity locally in the lower layer of the substrate; Applying a metal material on top of the heavily doped region of the second conductive impurity and the heavily doped region of the first conductive impurity; It is preferable to include the step of forming a front electrode and a back electrode on the front and rear surfaces of the substrate by the firing process.

In the forming of the highly doped region, it is preferable to perform a diffusion process using an impurity paste as a source.

In addition, forming the highly doped region may include locally patterning a second conductive impurity paste on the entire surface of the substrate; Locally patterning an impurity paste of a first conductivity type on a back side of the substrate; Performing a heat treatment process such that impurities contained in the second conductive type impurity paste and the first conductive type impurity paste are diffused into the substrate; Forming a passivation layer on the surface of the substrate except for a portion where the second conductive impurity paste and the first conductive impurity paste are patterned by the heat treatment process; It is preferable to include the step of forming an anti-reflection film on the front and rear surfaces of the substrate.

On the other hand, the manufacturing method of a double-sided light receiving localized emitter solar cell according to another embodiment of the present invention, preparing a substrate of the first conductive type; Forming a passivation layer on the surface of the substrate; Forming an anti-reflection film on the entire surface of the substrate; The anti-reflection film and the passivation layer formed on the front and rear surfaces of the substrate are locally removed by laser doping, and the high concentration doping region of the second conductive impurity is locally exposed on the upper layer of the substrate, and the lower layer of the substrate is formed. Locally exposing the high concentration doped region of the first conductivity type impurity; And forming an electrode to contact the exposed portion of the heavily doped region of the second conductive impurity and the heavily doped region of the first conductive impurity by performing a plating process.

The forming of the electrode may include depositing a seed layer that lowers a specific resistance to directly contact a high concentration doped region of the second conductive impurity and a high concentration doped region of the first conductive impurity, and It is preferable to plate the metal on the seed layer.

In the preparing of the substrate, it is preferable to proceed with a saw damage etching process and a texturing process.

According to the double-sided light receiving type localized emitter solar cell according to the present invention and a method of manufacturing the same, by forming a light receiving portion on the front and rear surfaces of the substrate, the light receiving portion of the substrate is increased to absorb even the sunlight reflected from the ground surface to absorb the sunlight. This can increase, thereby maximizing the efficiency of the solar cell.

In addition, according to the double-sided light receiving localized emitter solar cell and a method of manufacturing the same according to the present invention, by locally forming the emitter and the electrode on the front light receiving portion of the substrate, the recombination rate of the photo-generated minority transporter is reduced to reduce the minority transporter It can increase the lifetime of the battery, reduce the separation distance and the line width of the electrode to contact the emitter to collect a few carriers, and maximize the photoelectric conversion efficiency of the solar cell while ensuring maximum light receiving surface It works.

Further, according to the double-sided light receiving type localized emitter solar cell and the manufacturing method thereof according to the present invention, by forming the base and the electrode locally on the rear light receiving portion of the substrate, the front and rear surfaces of the substrate can be formed in the same structure, The occurrence of bending due to the high temperature process in solar cell manufacturing is reduced, which can minimize the breakage rate of the substrate during the solar cell manufacturing process using a thin substrate, and the metallic electrode on the back of the substrate By not forming, there is an effect that can reduce the manufacturing cost.

Further, according to the present invention, the double-sided light receiving type localized emitter solar cell and the manufacturing method thereof do not need to perform a cleaning process for removing an oxide film or an insulation process for forming a disconnection trench, thereby simplifying the process procedure. The manufacturing period can be shortened, and manufacturing cost can be reduced.

1 is a cross-sectional view showing the structure of a typical solar cell.
Figure 2 is a cross-sectional view showing the structure of a double-sided light receiving localized emitter solar cell according to an embodiment of the present invention.
3 is a process flowchart illustrating a method of manufacturing a double-sided light receiving localized emitter solar cell according to an embodiment of the present invention.
4 to 7 are cross-sectional views illustrating a method of manufacturing a double-sided light receiving type localized emitter solar cell according to an embodiment of the present invention.
8 to 10 are cross-sectional views illustrating a method of manufacturing a double-sided light receiving localized emitter solar cell according to another embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to a double-sided light receiving localized emitter solar cell and a manufacturing method according to a preferred embodiment of the present invention.

Referring to FIG. 2, a double-sided light receiving type localized emitter solar cell according to an embodiment of the present invention has a first conductive substrate made of a silicon material having a front electrode 14 and a rear electrode 15 on upper and lower surfaces thereof. And a high concentration doped region 10-2 of the second conductive impurity is locally formed on the upper layer of the substrate 10, and the front electrode 14 has a high concentration doped region of the second conductive impurity. It has a structure formed in contact with (10-2), a highly doped region 10-1 of the first conductivity type impurities is locally formed in the lower layer portion of the substrate 10, the back electrode 15 is the first conductivity type impurities Has a structure formed in contact with the heavily doped region 10-1. Here, the first conductivity type may be n type or p type, hereinafter, the first conductive type is p type, and the second conductive type is n type.

At this time, the highly doped region 10-2 of the second conductive type impurity forms a pn junction in the substrate 10, thereby enabling the movement of the minority carrier 1 photogenerated by solar incidence and thus the substrate 10. A potential difference can be generated inside the circuit), and the contact resistance between the metallic front electrode 14 and the interface of the substrate 10 is reduced.

The high concentration doped region 10-2 of the second conductive type impurity has a narrow spacing (for example, about 450 μm to 2300 μm) in order to reduce the moving distance of the few carriers generated in the substrate 10. If the distance between the front electrode 14 to be formed in contact with the upper surface is too narrow, there is a risk of shading loss due to the electrode, so the distance between the front electrode 14 to be formed in contact with the upper surface is reduced. It is preferable to be formed to have an appropriate width (for example, about 20 to 40 ㎛) in consideration.

Meanwhile, the high concentration doped region 10-1 of the first conductivity type impurity is formed in the lower layer of the substrate 10 to form a high-low junction in the substrate 10, whereby the minority carriers 1 that are photo-generated by solar incidence 1 At the same time to prevent the rear side movement, and serves to facilitate the movement of the plurality of carriers (2) collected by the rear electrode (15).

In addition, passivation layers 20 and 21 having dielectric properties are formed on upper and lower surfaces of the substrate 10, except for portions where the front electrode 14 and the rear electrode 15 are formed. The passivation layers 20 and 21 formed on the upper and lower surfaces include silicon oxide (SiO ₂ ), aluminum oxide (AlO ₃ ), titanium oxide (TiO ₂ ), or silicon nitride (Si ₃ N ₄ ) having dielectric properties. An anti-reflective coating (ARC) 13 is laminated.

In addition, the front electrode 14 may be formed in, for example, a finger line pattern, or the like, and may be formed at a position where a high concentration doped region 10-2 of a second conductive type impurity formed locally on an upper layer of the substrate 10 is formed. Since it is formed on the substrate 10 so as to correspond, it is preferably formed with a line width (W) of about 20㎛ 40㎛, the spacing (d) between the electrodes is preferably formed to be about 450㎛ 2300㎛.

That is, since the front electrode 14 according to the present invention has a line width of about 1/2 to 1/4 of the size of a general solar cell, the distance between electrodes is 1/2 of the gap between the front electrodes of a general solar cell. Even if it is narrowed to about 1/4, the light receiving surface of the same level as the light receiving surface of a general solar cell can be ensured.

On the other hand, the back electrode 15 may be formed, for example, in a pattern of a finger line shape and the like, and may be formed at a position where a high concentration doped region 10-1 of a first conductive type impurity formed locally in the lower layer of the substrate 10 is formed. It is formed under the substrate 10 so as to correspond. At this time, the back electrode 15 is formed with a line width (W ') of about 20㎛ 40㎛, it is preferable that the distance (d') between the electrodes is formed to be about 450㎛ 2300㎛.

Hereinafter, a method of manufacturing a double-sided light receiving type localized emitter solar cell according to an embodiment of the present invention will be described.

First, as shown in FIG. 3, a first conductive silicon substrate 10 is prepared (S100).

In step S100, a saw damage etching process of etching the substrate 10 in a chemical manner is performed in order to remove a defective portion generated as a result of the cutting process of the substrate 10. At this time, it is preferable to etch the surface of the substrate 10 by a predetermined depth using a potassium hydroxide (KOH) solution or the like as an etching solution, and then wash using DIW (Deionized Water).

In addition, after the saw damage etching (Saw Damage Etching) process, a wet texturing process or a dry texturing process using an acid or alkaline (Alkaline), etc. are performed. The surface uneven structure of the substrate 10 formed by such a texturing process is not shown in FIGS. 4 to 9 for the sake of simplicity.

In the state in which the substrate 10 is prepared through the above step S100, the highly doped region 10-2 of the second conductive type impurity is locally formed on the upper layer of the substrate 10 corresponding to the portion where the front electrode 14 is to be formed. Next, a high concentration doped region 10-1 of the first conductivity type impurity is locally formed in the lower layer of the substrate 10 corresponding to the portion where the rear electrode 14 is to be formed (S110).

In the step S110, an impurity ion implantation process or laser doping may be performed. However, in the present invention, as shown in FIGS. 4 to 5, the second conductive type impurity paste 5 and the first conductive type impurity may be used. A diffusion process is performed using the paste 6 as a source. In this case, the diffusion barrier may or may not be used.

That is, in step S110, as shown in FIG. 4, the second conductive type impurity paste 5 is locally patterned on the entire surface of the substrate 10, and the first conductive type is formed on the rear surface of the substrate 10. After the impurity paste 6 is locally patterned, a heat treatment process is performed such that impurities contained in the impurity paste 5 of the second conductivity type and the impurity paste 6 of the first conductivity type respectively diffuse into the substrate 10. As shown in FIG. 5, a heavily doped region 10-2 of the second conductive dopant, which is locally heavily doped, is formed on the upper layer of the substrate 10, and the lower layer of the substrate 10 is formed. It is preferable to form the heavily doped region 10-1 of the first conductive dopant locally doped with heavy doping.

The highly doped region 10-2 of the second conductive impurity formed in the upper layer portion of the substrate 10 through step S110 is formed of, for example, an n ++ region, and serves to form an electric field on the entire surface of the substrate 10. For example, the highly doped region 10-1 of the first conductive type impurity formed in the lower layer of the substrate 10 is formed of, for example, a p + region, and serves to form an electric field on the rear surface of the substrate 10. .

On the other hand, the surface of the substrate 10 except for the portion where the second conductive type impurity paste 5 and the first conductive type impurity paste 6 is patterned by the heat treatment during the diffusion process in step S110, that is, As shown in FIG. 5, the passivation layers 20 and 21 are naturally formed on the front and rear surfaces (S120).

After the above step S120, as shown in FIG. 6, antireflection films 13-1 and 13-2 are formed on the front and rear surfaces of the substrate 10 through a chemical vapor deposition process or the like (S130).

In forming the anti-reflection films 13-1 and 13-2 in step S130, it is preferable to use a Plasma Enhanced Chemical Vapor Deposition (PECVD) process. Here, the anti-reflection film 13 may be composed of a silicon nitride film (Si ₃ N ₄ ), for example, forming the silicon nitride film through a PECVD process, discharge and activate the source gas SiH ₄ and NH ₃ in a plasma state It can be implemented through a method for producing a silicon nitride film. In addition, the anti-reflection film 13 may be made of silicon oxide (SiO ₂ ), aluminum oxide (AlO ₃ ), titanium oxide (TiO ₂ ), or the like.

After the above step S130, as shown in FIG. 7 through the screen printing process, the front electrode 14 and the rear electrode 15 are formed on the front and rear surfaces of the substrate 10 (S140).

In the above-described step S140, as shown in FIG. 7, silver is disposed on the anti-reflection film 13-1 corresponding to the upper portion of the highly doped region 10-2 of the second conductive type impurity formed in the upper layer of the substrate 10. A front metal material 14-1 composed of (Ag) or the like, and the anti-reflection film 13- corresponding to the upper portion of the highly doped region 10-1 of the first conductivity type impurity formed in the lower layer of the substrate 10. 2) After applying the back metal material 15-1 including aluminum (Al), silver (Ag), and the like, the firing process is performed.

By the above-described steps S100 to S140 it can be finally produced a double-sided light receiving localized emitter solar cell as shown in FIG.

Alternatively, in a state where the substrate 10 is prepared through the above step S100, after performing the heat treatment process to perform the above step S120, the above step S130 is performed, and then, the front and rear surfaces of the substrate 10. 8 through a laser doping method capable of locally doping impurities on the upper and lower layers of the substrate 10 while locally removing the antireflection films 13-1 and 13-2 and the passivation layers 20 and 21 formed thereon. As shown, it is formed by exposing the high concentration doping region 10-2 of the second conductive impurity locally on the front surface of the substrate 10, and the high concentration of the first conductive impurity locally on the rear surface of the substrate 10. After exposing and forming the doped region 10-1, a plating process may be performed to contact the exposed portion of the highly doped region 10-2 of the second conductive type impurity formed on the upper layer of the substrate 10. 14 and a first conductive type fire formed in the lower layer of the substrate 10. By forming the back electrode 15 is in contact with the water exposed portions of the highly doped region (10-1), the double-sided light receiving type localized emitter as is finally shown in Figure 2 can be produced a solar cell emitter.

In this case, when the front electrode 14 and the back electrode 15 are formed, the exposed portions of the heavily doped region 10-2 of the second conductive impurity and the heavily doped region 10-1 of the first conductive impurity are respectively formed. The seed layers 14-2 and 15-2 which perform only metal plating to directly contact or lower the resistivity upon contact with the substrate 10 are heavily doped regions 10-2 of the second conductive type impurity. ) And the exposed portions of the heavily doped region 10-1 of the first conductivity type impurity, respectively, and then deposited on the seed layers 14-2 and 15-2 to metallize the front electrode 14 and The back electrode 15 may be formed. That is, as shown in FIGS. 9 to 10, the front electrode 14 and the rear electrode 15 may have seed layers 14-2 and 15-2 in the lower layer directly contacting the substrate 10, respectively. Can be.

The double-sided light-receiving localized emitter solar cell and the manufacturing method thereof according to the present invention are not limited to the above-described embodiments, and may be variously modified within the range allowed by the technical idea of the present invention.

1: minority carrier 2: majority carrier
5, 6: impurity paste 10: substrate
11: first conductive semiconductor layer 10-1: highly doped region of first conductive impurity
12: second conductive semiconductor layer 10-2: high concentration doped region of second conductive impurity
13, 13-1, 13-2: antireflection film 14: front electrode
14-1: front metal material 14-2, 15-2: seed layer
15: rear electrode 15-1: rear metal material
20, 21: passivation layer

Claims (11)

It includes a first conductive substrate having a front electrode and a rear electrode on the upper and lower surfaces,
A high concentration doped region of a second conductive impurity is locally formed in the upper layer of the substrate,
The front electrode is formed in contact with a high concentration doped region of the second conductive impurity,
A highly doped region of a first conductivity type impurity is locally formed in the lower layer of the substrate,
And the back electrode is formed in contact with a high concentration doped region of the first conductivity type impurity.
The method of claim 1,
A passivation layer is formed on upper and lower surfaces of the substrate except for a portion where the front electrode and the rear electrode are formed.
A double-sided light receiving localized emitter solar cell, wherein an anti-reflective coating (ARC) is stacked on the passivation layer.
The method according to claim 1 or 2,
And each of the front electrode and the rear electrode has a seed layer under the direct contact with the substrate.
The method according to claim 1 or 2,
The front electrode and the rear electrode is a double-sided light receiving localized emitter solar cell, characterized in that formed in the pattern of the finger line shape.
The method of claim 4, wherein
The front electrode is formed with a line width of 20㎛ 40㎛, double-sided light receiving localized emitter solar cell, characterized in that formed at intervals of 450㎛ to 2300㎛.
Preparing a substrate of a first conductivity type;
Forming a highly doped region of a second conductive impurity locally in an upper layer of the substrate;
Forming a heavily doped region of a first conductivity type impurity locally in the lower layer of the substrate;
Applying a metal material on top of the heavily doped region of the second conductive impurity and the heavily doped region of the first conductive impurity;
And forming a front electrode and a back electrode on the front and back surfaces of the substrate by firing.
The method of claim 6,
Forming the high concentration doped region,
A method for manufacturing a double-sided light receiving localized emitter solar cell, comprising performing a diffusion process using an impurity paste as a source.
The method of claim 7, wherein
Forming the high concentration doped region,
Locally patterning a second conductive impurity paste on the entire surface of the substrate;
Locally patterning an impurity paste of a first conductivity type on a back side of the substrate;
Performing a heat treatment process such that impurities contained in the second conductive type impurity paste and the first conductive type impurity paste are diffused into the substrate;
Forming a passivation layer on the surface of the substrate except for a portion where the second conductive impurity paste and the first conductive impurity paste are patterned by the heat treatment process;
And forming an anti-reflection film on the front and back surfaces of the substrate.
Preparing a substrate of a first conductivity type;
Forming a passivation layer on the surface of the substrate;
Forming an anti-reflection film on the entire surface of the substrate;
The anti-reflection film and the passivation layer formed on the front and rear surfaces of the substrate are locally removed by laser doping, and the high concentration doping region of the second conductive impurity is locally exposed on the upper layer of the substrate, and the lower layer of the substrate is formed. Locally exposing the high concentration doped region of the first conductivity type impurity;
Performing a plating process to form an electrode in contact with an exposed region of the heavily doped region of the second conductive impurity and the heavily doped region of the first conductive impurity; Emitter solar cell manufacturing method.
10. The method of claim 9,
Forming the electrode,
A seed layer for lowering the resistivity is deposited to directly contact the high concentration doped region of the second conductive impurity and the high concentration doped region of the first conductive impurity, and metal plating is performed on the seed layer. Method for manufacturing double-sided light receiving localized emitter solar cell.
The method according to any one of claims 6 to 10,
In the step of preparing the substrate,
A method of manufacturing a double-sided light receiving type localized emitter solar cell, comprising a saw damage etching process and a texturing process.

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