JP2002299576A - Method of manufacturing ferroelectric thin film element and ferroelectric thin film element - Google Patents

Abstract

(57) [Abstract] (Modified) [Problem] A method of manufacturing a ferroelectric thin film element in which a hydrogen barrier thin film material is produced by a method most suitable for the method and deterioration of element characteristics due to reduction of the ferroelectric thin film material is prevented. I will provide a. A hydrogen barrier film having good crystallinity is formed in advance on another substrate having good matching with the hydrogen barrier film, and this is transferred and formed on a ferroelectric thin film capacitor. The step of forming the hydrogen barrier thin film 206 on the ferroelectric thin film capacitor is A).
Step of forming an iridium oxide film 211 as a hydrogen barrier thin film on the surface of the substrate A; B) Metal B on the hydrogen barrier thin film
A step of forming a tin thin film 210; a step of bonding the upper electrode 209 of the ferroelectric thin film capacitor to the surface of the substrate A;
C) a step of transferring the hydrogen barrier thin film onto the ferroelectric thin film capacitor by peeling off the substrate A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION In recent years, ceramic thin films represented by PZT (lead zirconate titanate), ferroelectric memories and microactuators using them,
Research and development of ceramic thin film devices such as pyroelectric sensors have been actively conducted.

The present invention particularly relates to a ferroelectric thin film memory in which a memory cell is formed by a ferroelectric thin film capacitor formed on a semiconductor substrate for holding data and a switching transistor.

[0003]

2. Description of the Related Art A non-volatile memory element (ferroelectric memory element) utilizing spontaneous polarization peculiar to a ferroelectric material has characteristics such as high-speed writing / reading and low-voltage operation. , SRAM (static RAM) and D
It has the potential to replace most memories such as RAM. As a ferroelectric material, lead zirconate titanate (PZ
T) and other perovskite oxides and SrBi ₂ Ta ₂ O
Bismuth layered compounds such as ₉ have attracted attention.

In general, when the above-described oxide material is used as a capacitor insulating layer, it is covered with an interlayer insulating film such as SiO ₂ for the main purpose of electrical insulation between the memory elements after forming the upper electrode. In forming this film, when hydrogen generated as a reaction by-product reaches the ferroelectric thin film, the ferroelectric characteristics are significantly deteriorated by the reducing action. Also,
The characteristics of a MOS transistor as a switching element are degraded by lattice defects in a silicon single crystal generated in an element manufacturing process. Therefore, it is necessary to perform a heat treatment in a hydrogen-mixed nitrogen gas in a final stage. However, the hydrogen concentration in this step is higher than that during the formation of the interlayer insulating film, and the damage to the ferroelectric thin film becomes more serious.

As a means for overcoming such problems, a method has been proposed in which a thin film exhibiting a barrier effect against hydrogen is formed on the upper electrode of a ferroelectric thin film capacitor to protect the ferroelectric thin film from a hydrogen atmosphere. ing. As a film forming technique, as shown in JP-A-11-126883 and JP-A-11-8355, a desired material is generally formed on the upper electrode by sputtering or the like.

[0006]

Oxide materials have been energetically studied as potential candidates for hydrogen barrier films. IrOx is a typical example, and its reduction resistance has been investigated. For example, J. Electrochem. Soc. 136, 1740 (1989) and Surface Sc
In ience 144, 451 (1984), the resistance to a reducing atmosphere is examined between IrOx films formed by different film forming methods. According to these reports, the ease of reduction greatly differs depending on the crystallinity, and IrOx with better crystallinity has better hydrogen resistance. For example, it is reported that an IrOx thin film obtained by oxidizing the surface of single-crystal Ir is not reduced even in a high-temperature hydrogen atmosphere near 700 ° C. If such an IrOx thin film having good crystallinity is used as a hydrogen barrier film, it is difficult to be easily reduced even in a hydrogen atmosphere, and a sufficient effect as a hydrogen barrier can be expected.

However, as described above, a technique such as sputtering is generally used for forming IrOx. Usually Ir
Perform reactive sputtering using a metal target.
The crystallinity of IrOx obtained in this case is limited. As-d
Although post-annealing is effective to increase the degree of oxidation from the state of epo, treatment in an oxygen atmosphere at a high temperature may damage the CMOS substrate, so that the treatment temperature is limited. The conventional method has a problem in that an oxide film exhibiting a sufficient barrier effect against a hydrogen atmosphere cannot be obtained.

The method for manufacturing a ferroelectric thin film element of the present invention comprises:
It is an object of the present invention to prevent deterioration of device characteristics due to reduction of a ferroelectric thin film material by producing a thin film material exhibiting a barrier effect against hydrogen by a method most suitable for the thin film material.

[0009]

According to the present invention, there is provided a method of manufacturing a ferroelectric thin film device, comprising: 1) stacking a lower electrode, a ferroelectric thin film, and an upper electrode on a CMOS circuit board; A step of manufacturing a thin film capacitor, 2) a step of forming a thin film having a barrier effect against hydrogen on the ferroelectric thin film capacitor, and 3) a desired laminated structure obtained by the steps 1) and 2). Patterning into a shape; 4) a method of manufacturing a ferroelectric thin-film element including a step of electrically connecting the ferroelectric thin-film capacitor to an element provided on the CMOS circuit board. A) a step of forming a thin film having a barrier effect against hydrogen on the surface of the substrate A; B) a step of forming a metal B on the thin film having a barrier effect against hydrogen; C) the ferroelectric substance Upper electrode and front of thin film capacitor A step of bonding the surface of the substrate A, C), characterized by comprising the step of transferring a thin film showing a barrier effect with respect to the hydrogen on the ferroelectric thin film on the capacitor by peeling the substrate A.

According to the above-mentioned method, a thin film exhibiting a barrier effect against hydrogen can be produced under the most suitable film forming conditions. It has the effect that the effect is maximized.

A method of manufacturing a ferroelectric thin film element according to a second aspect is characterized in that the substrate A is a single crystal.

According to the above method, the crystallinity of a thin film exhibiting a barrier effect against hydrogen can be improved, so that the barrier effect can be improved.

The method of manufacturing a ferroelectric thin film element according to claim 3, wherein the step A) comprises: D) forming a metal thin film D on a substrate A; and E) oxidizing the metal thin film D. It is characterized by becoming.

According to the above method, the crystallinity of the oxide thin film exhibiting a barrier effect against hydrogen can be improved, so that an excellent barrier effect can be obtained.

According to a fourth aspect of the present invention, in the method of manufacturing a ferroelectric thin film element, the outermost surface of the upper electrode of the ferroelectric thin film capacitor is tin.

According to the above method, there is an effect that a thin film having a barrier effect against hydrogen formed on the substrate A is transferred onto the ferroelectric thin film capacitor with good reproducibility.

According to a fifth aspect of the present invention, in the method of manufacturing a ferroelectric thin film element, the metal B is platinum.

According to the above method, the thin film having a barrier effect against hydrogen formed on the substrate A is transferred to the ferroelectric thin film capacitor with higher reproducibility.

According to a sixth aspect of the present invention, in the method of manufacturing a ferroelectric thin film element, the metal B is gold.

According to the above method, the thin film having a barrier effect against hydrogen formed on the substrate A is transferred onto the ferroelectric thin film capacitor with good reproducibility, and a stable adhesion force is maintained even during the subsequent process. It has the effect of being maintained.

According to a seventh aspect of the present invention, in the method of manufacturing a ferroelectric thin film element, the metal B is tin.

According to the above method, there is an effect that a thin film having a barrier effect against hydrogen formed on the substrate A is transferred onto the ferroelectric thin film capacitor with good reproducibility.

[0023] A method of manufacturing a ferroelectric thin film element according to claim 8 is characterized in that the outermost surface of the upper electrode of the ferroelectric thin film capacitor is platinum.

According to the above-described method, there is an effect that a thin film formed on the substrate A and exhibiting a barrier effect against hydrogen is transferred onto the ferroelectric thin film capacitor with higher reproducibility.

According to a ninth aspect of the present invention, in the method of manufacturing a ferroelectric thin film element, the outermost surface of the upper electrode of the ferroelectric thin film capacitor is made of gold.

According to the above method, a thin film having a barrier effect against hydrogen formed on the substrate A is transferred onto the ferroelectric thin film capacitor with good reproducibility, and a stable adhesion force is maintained even during the subsequent process. It has the effect of being maintained.

According to a tenth aspect of the present invention, in the method of manufacturing a ferroelectric thin film element, the metal thin film D is iridium.

According to the above method, there is an effect that IrOx having good crystallinity can be provided on a ferroelectric thin film capacitor as a thin film having a barrier effect against hydrogen.

Further, the ferroelectric thin-film element manufactured by the manufacturing method of the present invention exhibits extremely excellent element performance because there is no deterioration of the ferroelectric material characteristics due to hydrogen generated during the process. Has an effect.

[0030]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) First, a laminating process of a ferroelectric thin film element will be schematically described with reference to FIGS.

On a single crystal silicon substrate 201, a MOS transistor serving as a switching transistor 202 and an element isolation region 203 were formed, and a boron phosphorus-doped silicon oxide film (BPSG) 204 was formed as an interlayer insulating film.

Next, after a resist pattern for forming a contact hole was formed by a lithography process, the contact hole was opened by a dry etching method. After depositing the polysilicon film, phosphorus was doped. Subsequently, the polysilicon film was polished by chemical mechanical polishing to form a polysilicon plug 205 in the contact hole.

Next, a titanium nitride film was formed as a barrier metal layer 206 between the lower electrode and the polysilicon plug 205 by a sputtering method. Iridium was formed thereon as a lower electrode 207.

A sol solution was prepared as a precursor solution of the ceramic thin film. 2-n-butoxyethanol was used as the main component of the solvent, and lead acetate trihydrate, zirconium acetylacetonate and titanium tetraisopolopoxide were dissolved in appropriate amounts to adjust to a desired concentration. This raw material sol was applied onto the lower electrode 207 by spin coating, and dried at an appropriate temperature. A precursor film having a desired film thickness is formed by repeating the application and drying of the sol liquid. This was finally baked at 750 ° C. for 1 minute to obtain a lead zirconate titanate (hereinafter referred to as PZT) thin film 208. Further, iridium was formed as the upper electrode 209 by sputtering. FIG. 2 shows the laminated structure of the thin films obtained by the above steps.

An iridium oxide film (IrOx) 211 was formed on the substrate A (215) by reactive sputtering. Oxygen annealing at 800 ° C. for 30 minutes was performed to improve the crystallinity by further oxidizing. A tin thin film 210 was formed thereon by sputtering (see FIG.
3).

The surface of the tin thin film 210 formed on the substrate A is fluorinated with hydrogen fluoride (HF). An outline of the processing method is shown in FIG. In this embodiment, CF ₄ is used as a source gas for generating HF. This gas is first mixed with H ₂ O by the container 101 and subsequently sent to the discharge unit 102. Here, H ₂ O and CF ₄ are decomposed, and at the same time, reactive HF is generated as a secondary product. This HF is sent together with H ₂ O into the fluoridation vessel 103 which has been replaced by nitrogen in advance. The surface of the sample 106 which is heated to an appropriate temperature by the heater _{104, 2HF + H 2 O →} HF 2 - + H 3 O + of the reaction occurs, HF ₂ ^- the sample surface by is fluoride.
Here, the surface of the tin film formed on the substrate A was fluorinated.

The silicon substrate 201 and the substrate A (215) were overlapped, and an appropriate pressure was applied while heating both substrates. FIG. 4 shows a schematic diagram of a cross section of the sample. First, fluorine atoms are bonded to the surface of the tin thin film 210, but when a certain temperature is reached, the bonding starts to be broken. Instead, the tin combines with iridium of the upper electrode 209 to form a eutectic of tin and iridium. The formation of a eutectic on the entire bonding surface makes the bonding stronger. After a sufficient time had elapsed, the substrates were separated from each other, and as shown in FIG. 5, the substrates A (215) and I
Separation occurs at the interface with the rOx thin film 211, and the IrOx thin film 211
Was transferred from the substrate A (215) onto the upper electrode 209 of the ferroelectric thin film.

Next, a lower electrode, a PZT thin film, an upper electrode and IrOx
The thin film was patterned to a desired size. A TEOS (Tetr (Tetr)
aethylorthosilicate) film was deposited. After providing an opening for obtaining electrical contact with the upper electrode of the ferroelectric thin film capacitor, a metal wiring 213 was formed. FIG. 6 shows the obtained device structure. This is particularly called a stack type and is one of the memory cell structures aimed at high integration (sample 1).

On the other hand, a ferroelectric memory cell having a similar structure was manufactured by a conventional method for comparison. That is, when the IrOx thin film was provided on the upper electrode of the ferroelectric thin film capacitor, it was directly deposited here by the sputtering method. The structure of the finally obtained memory element is the same as that of FIG. 6 except that the tin thin film is not included in the laminated structure (sample 2).

The performance of the memory devices obtained by each method was compared. In this example, a hysteresis curve was examined to pay attention to the characteristics of the ferroelectric thin film capacitor. FIG. 7 shows the results.

As is apparent from the figure, the ferroelectric thin film capacitor obtained by the method of the present invention shows better hysteresis characteristics than those obtained by the conventional method. In particular, the amount of remanent polarization is much larger than the capacitor obtained by the conventional method, which is extremely advantageous in securing the stability of the memory operation.

When the interlayer insulating film 212 is formed, hydrogen is generated. IrOx was formed as a barrier layer for the purpose of preventing this hydrogen from reaching the ferroelectric thin film capacitor, but it is considered that a remarkable difference in the barrier effect appeared due to the difference in the film formation method. In the method of the present invention, IrOx is once deposited on another substrate instead of the circuit substrate. At this stage, the high-temperature treatment can be performed in an oxygen atmosphere without considering the damage on the circuit side, so that a sufficiently oxidized film is manufactured. Such an IrOx film can maximize the barrier effect against hydrogen. When this is provided on the ferroelectric capacitor by transfer, it completely protects the ferroelectric thin film from the hydrogen atmosphere. Therefore, the ferroelectric characteristics did not deteriorate, and an extremely high performance memory element was obtained.

Example 2 A ferroelectric thin film capacitor was formed on a circuit board in which a switching transistor was incorporated by the same method as in Example 1 (FIG. 8).

As a substrate A, a single crystal (100) Si substrate 415 was prepared. On top of this, YSZ (Yttr
ia Stabilized Zirconia) 416 was heteroepitaxially grown. Further, an iridium (Ir) thin film 417 was deposited thereon by sputtering. FIG. 9 shows the obtained laminated structure.

First, in order to examine the crystallinity of the iridium thin film, an X-ray diffraction pattern was obtained by a wide angle method. The observed iridium diffraction peak was only from the (100) plane, and it was expected that the formed Ir thin film was (100) oriented. In order to further investigate the crystallinity details,
I decided to study the rocking curve of Ir (200). I
r The angle of incidence of X-rays on the thin film surface is denoted by θ, and the deviation from θ is denoted by Δθ. When the diffraction intensity from the (200) plane was measured within the range of Δθ = ± 10 °, a sharp peak having a half-value width of about 1 ° around Δθ = 0 ° was observed. From the above, it became clear that the Ir thin film formed on YSZ was a (100) strongly oriented film reflecting the crystallinity of the underlying substrate.
Next, the iridium thin film was subjected to a temporary heat treatment in an oxygen atmosphere to obtain an IrOx thin film 411. A tin thin film 410 was formed thereon by sputtering (see FIG. 1).
0). Subsequently, the surface of the tin thin film 410 was subjected to a fluorination treatment in the same manner as described in Example 1.

The silicon substrate 401 and the Si (100) substrate 415 were overlaid, and an appropriate pressure was applied while heating both substrates.
FIG. 11 shows a schematic diagram of a cross section of the sample. First, fluorine atoms are bonded to the surface of the tin thin film 410, but when a certain temperature is reached, the bonding starts to be broken. Instead, tin combines with iridium of the upper electrode 409, and a eutectic of tin and iridium is formed. The formation of a eutectic on the entire bonding surface makes the bonding stronger. After a sufficient time had passed, the substrates were separated from each other, and as shown in FIG.
Separation occurs at the interface between the 16 and the IrOx thin film 411, and the IrOx thin film 411 is moved from the Si (100) substrate 415 to the upper electrode 409 of the ferroelectric thin film.
Transcribed up.

Next, a lower electrode, a PZT thin film, an upper electrode and IrOx
The thin film was patterned to a desired size. On this, TEOS (Tetr (Tetr
aethylorthosilicate) film was deposited. After providing an opening for obtaining electrical contact with the upper electrode of the ferroelectric thin film capacitor, a metal wiring 413 was formed. FIG. 13 shows the obtained device structure.

The performance of the memory device was compared with the device obtained by the method of the first embodiment. Here, after applying a predetermined voltage to the ferroelectric thin film capacitor, the remanent polarization (Re
The size of manent Polarization (Pr) was examined. It can be said that the larger this value is, the more excellent the ferroelectric property is. Table 1 shows the results.

[0050]

[Table 1] As is clear from Table 1, the device obtained in this example shows a larger Pr. This is extremely advantageous in securing the stability of the memory operation.

When the interlayer insulating film 412 is formed, hydrogen is generated. IrOx was formed as a barrier layer on the upper electrode in order to prevent the hydrogen from reaching the ferroelectric thin film capacitor, but it is considered that a difference in the barrier effect appeared due to a difference in crystallinity. The IrOx thin film used in this example is manufactured by thermally oxidizing iridium formed on a substrate by controlling the orientation. The device performance was further improved because IrOx having excellent crystallinity exhibited more effective hydrogen barrier properties.

Example 3 In the same manner as in Example 1, a lower electrode and a ferroelectric thin film were formed on a circuit board having a switching transistor incorporated therein. Further, as an upper electrode, a tin (Sn) thin film was formed by sputtering (FIG. 14). Subsequently, the tin surface was fluorinated in the same manner as described in Example 1.

As a substrate A, a single crystal (100) Si substrate 515 was prepared. On top of this, YSZ (Yttr
ia Stabilized Zirconia) 516 was heteroepitaxially grown. Further, an iridium (Ir) thin film 517 was deposited thereon by sputtering. FIG. 15 shows the obtained laminated structure. This was annealed in an oxygen atmosphere for about one hour to obtain an IrOx thin film 511. Platinum 510 was formed thereon by sputtering (FIG. 16).

The silicon substrate 501 and the Si (100) substrate 515 were overlaid, and an appropriate pressure was applied while heating both substrates.
FIG. 17 shows a schematic diagram of a cross section of the sample. Initially, fluorine atoms are bonded to the surface of the tin thin film 509, but when a certain temperature is reached, the bonding starts to be broken. Instead, the tin combines with the platinum 510 to form a eutectic of tin and platinum. The formation of a eutectic on the entire bonding surface makes the bonding stronger. After a sufficient time has passed, the boards are separated from each other.
As shown in FIG. 18, separation occurs at the interface between the YSZ thin film 516 and the IrOx thin film 511, and the IrOx thin film 511 is removed from the Si (100) substrate 515.
It was transferred onto the upper electrode 509 of the ferroelectric thin film from above.

Next, a lower electrode, a PZT thin film, an upper electrode and IrOx
The thin film was patterned to a desired size. On this, TEOS (Tetr (Tetr
aethylorthosilicate) film was deposited. After providing an opening for obtaining electrical contact with the upper electrode of the ferroelectric thin film capacitor, a metal wiring 513 was formed. FIG. 19 shows the obtained device structure.

The non-defective rate of the element was compared between the method shown in the present embodiment and the method shown in the second embodiment. The number of devices fabricated for quantitative comparison is defined as N, and the number of devices capable of observing sufficient ferroelectric properties is defined as X. Table 2 summarizes the ratio of X to N.

[0057]

[Table 2] As is evident from Table 2, the non-defective product ratio is higher in the device configuration shown in this embodiment. Observation of a cross section of a defective element among the memory elements (FIG. 19) manufactured by using the method described in Example 2 showed that Ir was placed on the ferroelectric thin film capacitor.
Ox was not formed. It is conceivable that the capacitor was peeled off from the upper electrode in the patterning step. In this case, when the interlayer insulating film is formed in the next step, hydrogen passes through the upper electrode and reaches the ferroelectric thin film. The ferroelectric characteristics of the capacitor will be significantly deteriorated, and the performance of the device as a memory cannot be expected.

When the device configuration is compared between the present embodiment and the second embodiment, the difference is in the material to be bonded to tin in each laminated structure. In Example 2, tin was bonded to Ir,
In this embodiment, it is bonded to platinum. It is considered that there was a difference in the bonding strength due to the difference in the easiness of eutectic formation.
Providing a eutectic interface between platinum and tin having a higher bonding strength in the laminated structure as in the element configuration of the present embodiment is the same as IrOx.
It has been found that it is very important to form a thin film on a ferroelectric thin film capacitor with good reproducibility.

In this embodiment, platinum is bonded to Sn, but it may be bonded to gold. In this case, since the bonding strength is further improved, the transfer formation of IrOx becomes more reliable.

(Example 4) In the same manner as in Example 1, a lower electrode and a ferroelectric thin film were formed on a circuit board in which a switching transistor was incorporated. Further, a platinum (Pt) thin film was formed by sputtering as an upper electrode (FIG. 20).

As a substrate A, a single crystal (100) Si substrate 615 was prepared. On top of this, YSZ (Yttr
ia Stabilized Zirconia) 616 was heteroepitaxially grown. Further, an iridium (Ir) thin film 617 was deposited thereon by sputtering. FIG. 21 shows the obtained laminated structure. This was annealed in an oxygen atmosphere for about one hour to obtain an IrOx thin film 611. A tin thin film 610 was formed thereon by sputtering (FIG. 22). The tin surface was fluorinated in the same manner as described in Example 1.

The silicon substrate 601 and the Si (100) substrate 615 were overlaid, and an appropriate pressure was applied while heating both substrates.
FIG. 23 shows a schematic diagram of a cross section of the sample. Initially, fluorine atoms are bonded to the surface of the tin thin film 610, but when a certain temperature is reached, the bonding starts to be broken. Instead, the tin combines with the platinum 609 to form a eutectic of tin and platinum. The formation of a eutectic on the entire bonding surface makes the bonding stronger. After a sufficient time has passed, the boards are separated from each other.
As shown in FIG. 24, peeling occurs at the interface between the YSZ thin film 616 and the IrOx thin film 611, and the IrOx thin film 611 becomes a Si (100) substrate 615.
It was transferred onto the upper electrode 609 of the ferroelectric thin film from above.

Next, a lower electrode, a PZT thin film, an upper electrode and IrOx
The thin film was patterned to a desired size. TEOS (Tetr (Tetr)
aethylorthosilicate) film was deposited. After providing an opening for obtaining electrical contact with the upper electrode of the ferroelectric thin film capacitor, a metal wiring 613 was formed. FIG. 25 shows the obtained device structure.

The non-defective rate of the element was compared between the method shown in the present embodiment and the method shown in the second embodiment. The number of devices fabricated for quantitative comparison is defined as N, and the number of devices capable of observing sufficient ferroelectric properties is defined as X. Table 3 summarizes the ratio of X to N.

[0065]

[Table 3] As is clear from Table 3, the non-defective rate is higher in the element configuration shown in this example. When a cross section of a defective memory device (FIG. 25) manufactured using the method described in Example 2 was observed, Ir was found to be on the ferroelectric thin film capacitor.
Ox was not formed. It is conceivable that the capacitor was peeled off from the upper electrode in the patterning step. In this case, when the interlayer insulating film is formed in the next step, hydrogen passes through the upper electrode and reaches the ferroelectric thin film. The ferroelectric characteristics of the capacitor will be significantly deteriorated, and the performance of the device as a memory cannot be expected.

When the device configuration is compared between the present embodiment and the second embodiment, the difference is in the material to be bonded to tin in each laminated structure. In Example 2, tin was bonded to Ir,
In this embodiment, it is bonded to platinum. It is considered that there was a difference in the bonding strength due to the difference in the easiness of eutectic formation.
Providing a eutectic interface between platinum and tin having a higher bonding strength in the laminated structure as in the element configuration of the present embodiment is the same as IrOx.
It has been found that it is very important to form a thin film on a ferroelectric thin film capacitor with good reproducibility.

In this embodiment, platinum is bonded to Sn, but it may be bonded to gold. In this case, since the bonding strength is further improved, the transfer formation of IrOx becomes more reliable.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a fluoridation process.

FIG. 2 is a view showing a manufacturing process of a ferroelectric thin film element in Example 1.

FIG. 3 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 1.

FIG. 4 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 1.

FIG. 5 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 1.

FIG. 6 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 1.

FIG. 7 is a diagram showing hysteresis characteristics of a ferroelectric thin film capacitor.

FIG. 8 is a diagram showing a manufacturing process of a ferroelectric thin film element in Example 2.

FIG. 9 is a view showing a manufacturing process of the ferroelectric thin film element in Example 2.

FIG. 10 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 2.

FIG. 11 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 2.

FIG. 12 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 2.

FIG. 13 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 2.

FIG. 14 is a diagram illustrating a manufacturing process of the ferroelectric thin-film element in the third embodiment.

FIG. 15 is a diagram showing a manufacturing process of the ferroelectric thin-film element in the third embodiment.

FIG. 16 is a diagram illustrating a manufacturing process of the ferroelectric thin film element in the third embodiment.

FIG. 17 is a diagram showing a manufacturing process of the ferroelectric thin-film element in Example 3.

FIG. 18 is a diagram illustrating a manufacturing process of the ferroelectric thin-film element in the third embodiment.

FIG. 19 is a diagram illustrating a manufacturing process of the ferroelectric thin-film element in the third embodiment.

FIG. 20 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 4.

FIG. 21 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 4.

FIG. 22 is a diagram showing a manufacturing process of the ferroelectric thin-film element in Example 4.

FIG. 23 is a diagram showing a manufacturing process of the ferroelectric thin film element in Example 4.

FIG. 24 is a diagram showing a manufacturing process of the ferroelectric thin-film element in Example 4.

FIG. 25 is a diagram illustrating a manufacturing process of the ferroelectric thin-film element in Example 4.

[Explanation of symbols]

101. Vessel for mixing CF ₄ and H ₂ O 102. Discharge unit 103. Container for fluorination treatment 104. Heater for heating the sample 105. Exclusion device 106. Sample 201. Silicon substrate 202. Switching transistor 203. Element isolation region 204. Interlayer insulating film 205. Polysilicon plug 206. Barrier metal layer 207. Lower electrode 208. PZT thin film 209. Upper electrode 210. Tin thin film 211. IrOx thin film 212. Interlayer insulating film 213. Metal wiring 214. Protective film 215. Substrate A 401. Silicon substrate 402. Switching transistor 403. Element isolation region 404. Interlayer insulating film 405. Polysilicon plug 406. Barrier metal layer 407. Lower electrode 408. PZT thin film 409. Upper electrode 410. Tin thin film 411. IrOx thin film 412. Interlayer insulating film 413. Metal wiring 414. Protective film 415. Si (100) substrate 416. YSZ thin film 417. Ir thin film 501. Silicon substrate 502. Switching transistor 503. Element isolation region 504. Interlayer insulating film 505. Polysilicon plug 506. Barrier metal layer 507. Lower electrode 508. PZT thin film 509. Upper electrode 510. Platinum 511. IrOx thin film 512. Interlayer insulating film 513. Metal wiring 514. Protective film 515. Si (100) substrate 516. YSZ thin film 517. Ir thin film 601. Silicon substrate 602. Switching transistor 603. Element isolation region 604. Interlayer insulating film 605. Polysilicon plug 606. Barrier metal layer 607. Lower electrode 608. PZT thin film 609. Upper electrode 610. Tin thin film 611. IrOx thin film 612. Interlayer insulating film 613. Metal wiring 614. Protective film 615. Si (100) substrate 616. YSZ thin film 617. Ir thin film

 ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Katsuhiro Takahashi 3-5-5 Yamato, Suwa-shi, Nagano F-term in Seiko Epson Corporation (reference) 4M104 AA01 BB01 BB04 BB06 BB30 BB36 BB37 BB40 CC01 DD08 DD16 DD19 DD22 DD37 DD55 DD64 DD65 DD75 DD78 DD83 DD86 FF18 GG16 GG19 HH08 HH20 5F033 HH07 HH33 JJ01 JJ04 JJ07 KK01 KK07 KK13 KK35 LL04 LL07 MM05 MM08 MM13 PP15 PP16 QQ08 QQ09 QQ10 QQ11 QQ37 QQ48 QQ59 QQ65 QQ69 QQ73 QQ76 QQ86 RR04 RR15 SS04 SS15 TT02 VV10 VV16 XX00 XX13 5F083 AD21 FR02 GA21 GA25 JA15 JA39 JA40 JA43 MA06 PR18 PR22 PR23 PR25 PR33 PR40

Claims (11)

[Claims] 1) a step of fabricating a ferroelectric thin film capacitor by laminating a lower electrode, a ferroelectric thin film and an upper electrode on a CMOS circuit board; 2) preventing hydrogen on the ferroelectric thin film capacitor. 3) a step of patterning the laminated structure obtained by the steps 1) and 2) into a desired shape, 4) the ferroelectric thin film capacitor and the CMOS circuit board. In the method of manufacturing a ferroelectric thin film element including a step of electrically connecting the element provided in the step (a), the step (2) includes the step (A) of forming a thin film having a barrier effect against hydrogen on the surface of the substrate (A). Process,
B) a step of forming a metal B on the thin film having a barrier effect against hydrogen; C) a step of bonding an upper electrode of the ferroelectric thin film capacitor to a surface of the substrate A;
And transferring a thin film exhibiting a barrier effect against hydrogen to the ferroelectric thin film capacitor by peeling off the thin film on the ferroelectric thin film capacitor. 2. The method for manufacturing a ferroelectric thin film element according to claim 1, wherein said substrate A is a single crystal. 3. The method according to claim 1, wherein the step A) comprises: D) a step of forming a metal thin film D on the substrate A; and E) a step of oxidizing the metal thin film D. The manufacturing method of the ferroelectric thin film element according to the above. 4. The method according to claim 1, wherein the outermost surface of the upper electrode of the ferroelectric thin film capacitor is tin. 5. The method for manufacturing a ferroelectric thin film element according to claim 1, wherein said metal B is platinum. 6. The method for manufacturing a ferroelectric thin film device according to claim 1, wherein said metal B is gold. 7. The method for manufacturing a ferroelectric thin film device according to claim 1, wherein said metal B is tin. 8. The method according to claim 7, wherein the outermost surface of the upper electrode of the ferroelectric thin film capacitor is platinum. 9. The method according to claim 7, wherein the outermost surface of the upper electrode of the ferroelectric thin film capacitor is gold. 10. The method according to claim 3, wherein said metal thin film D is iridium. 11. A ferroelectric thin-film device produced by the method according to claim 1. Description: