JP2001026500A - Deposition of thin-film single crystal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method which prevents the degradation in quality of a single crystal layer and the degradation in yield when the single crystal layer for depositing a semiconductor device is peeled as a thin film. SOLUTION: A release layer 102, such as a porous layer, and a thin-film single crystal 103, such as an epitaxially grown silicon layer, are formed by on the surface of a substrate 1, such as a silicone wafer, the arrangement in this order. A sheet-like member 104 is stuck to the surface of the thin-film single crystal or a layer additively formed thereon. Force is applied to this sheet-like member so as to curve the member, by which the thin-film single crystal is peeled from the substrate. At this time, the peeling of the thin-film single crystal is so progressed that the direction of all the straight lines formed by the appearance of the most easily peelable faces, such as 111} faces, of this thin-film single crystal on the surface of the thin film and the direction of the foremost line at which the thin-film single crystal peels from the substrate forms an angle of >=5 deg.. A solar battery, image display element drive circuit part, etc., are produced by utilizing such thin-film single crystal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a thin film single crystal device. The thin film single crystal device includes a solar cell and a member for an image display element driving circuit of a liquid crystal display element.

[0002]

2. Description of the Related Art Solar cells are becoming widespread as independent power supplies for driving various electric devices and as power supplies for system interconnection with commercial power. Generally, silicon or gallium arsenide is used as a semiconductor constituting a solar cell. In order to obtain particularly high photoelectric conversion efficiency (the efficiency of converting light energy into electric power), it is preferable to use single crystals of these semiconductors.

Recently, in a large-area image display device such as a liquid crystal image display device, the performance of a driving circuit built in the device has been required to be improved due to demands for miniaturization and high-speed operation. For that purpose, it is better to form the drive circuit in single-crystal silicon than in the amorphous or polycrystalline silicon conventionally used.

However, there are some problems in using a single crystal semiconductor for such a purpose. When silicon is used for a solar cell, the thickness required for absorbing incident sunlight is about 30 to 50 μm, whereas a generally used single crystal wafer has a thickness of about 300 to 600 μm. In particular, when silicon crystals used for solar cells occupy 10% or more of the total production amount as in recent years, it is desired to reduce the amount of materials used. Further, in the image display device, light must be transmitted in a region between the elements in the drive circuit due to its use form, but it is difficult to form such a structure with a general single crystal wafer. is there.
Moreover, the thickness of the single crystal layer required for the driving element itself is 1 μm.
Below m, the underlying silicon only serves as a support substrate.

To solve such a problem, a thin film single crystal having a thickness suitable for the purpose may be used. However, it is difficult to produce a single crystal layer having a thickness of 300 μm or less by the conventional technology. there were. That is, the conventional method of manufacturing a single crystal substrate grows an ingot-like single crystal from a melt of the crystal material,
Because this was sliced and polished thinly, the thickness was 300
It was difficult to reduce the thickness to less than μm. Further, in order to obtain a high-quality thin-film single crystal for a special purpose, a single-crystal substrate having a thickness of several hundred μm is etched from the back surface to a desired thickness. There were many. However, recently, a thin film single crystal epitaxially grown on the surface of a single crystal substrate has been peeled off from the substrate by using the method described in Japanese Patent Application Laid-Open No. 7-302889.
By using the technology described in Japanese Patent No. 333077, a portion within a certain range from the surface of the single crystal substrate can be peeled as a thin film. However, even in these methods,
When the thin film single crystal is separated from the substrate, the quality of the thin film single crystal is reduced due to defects in the thin film single crystal, and in severe cases, the thin film single crystal is cracked and the production yield is significantly reduced, which is effective. A solution was desired.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a method of peeling a thin film single crystal from a substrate without generating defects or cracks in the production of a thin film single crystal device. It is an object to make it possible to manufacture a crystal device with a high yield.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and have finally completed the present invention.

That is, in the present invention, a release layer and a thin film single crystal are formed on the surface of a substrate in this order,
A flexible sheet member is attached to the surface of the thin film single crystal or a layer additionally formed on the surface of the thin film single crystal, and a force is applied so as to bend the sheet member. A method of manufacturing a thin film single crystal device using the thin film single crystal by peeling the thin film single crystal from the substrate, wherein the thin film single crystal is most cleaved when the thin film single crystal is peeled from the substrate. The separation of the thin film single crystal is advanced so that the direction of all the straight lines formed on the surface of the thin film does not coincide with the forefront of the separation, thereby preventing the occurrence of defects and cracks. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the case where the present invention is applied to the production of a thin-film single-crystal silicon solar cell using a porous layer as a release layer will be described, but the present invention relates to other thin-film single-crystal devices. It is also applicable to the manufacturing method. FIG. 3 is a process diagram showing a process of manufacturing a thin-film single-crystal silicon solar cell using a porous layer as a release layer.

In step a), a single-crystal silicon wafer is used as a substrate 301, and the surface is immersed in a hydrofluoric acid solution and a positive potential is applied.
Over a depth of m, a large number of micropores interconnected irregularly are formed. This is called a porous layer 302. The porous layer 302 keeps a single crystal property, and a thermal CVD
In step b), the first single crystal layer 303
Then, the second single crystal layer 304 can be epitaxially grown in the step c). Here, 303 is a weak p-type (p
^- a mold), 304 strong n-type (n ⁺ -type). 303
And 304 form a pn junction, and the action of this junction produces a photovoltaic. 304 represents 30 in step c).
Alternatively, a layer containing an n-type dopant may be formed on the surface of No. 3, and the n-type dopant may be thermally diffused from this layer.

Thereafter, in step d), the anti-reflection layer 30
5. A grid electrode 306 is formed. Next, when a force is applied to the single crystal layer in the step e), a cut occurs inside the porous layer 302 which has become brittle due to the formation of the holes, and the portion above the first single crystal layer 303 is the substrate. 30
Peel from the main part of No. 1. Note that, in FIG. 3, the substrate 301 is illustrated to have a thickness equivalent to that of the first single crystal layer 303 and the second single crystal layer 304 for the sake of explanation.
About 100 μm, and the porous layer 302 or the first single crystal layer 30
3. It is much thicker than the second single crystal layer 304. A part of the porous layer 302 may remain on the back surface of the peeled first single crystal layer 303, but the removal is not necessarily required. Thereafter, in step f), a back electrode 3 is formed on the back surface of the first single crystal layer 303 using a conductive adhesive having a high light reflectance.
07 is pasted. Thus, a thin-film single-crystal silicon solar cell is completed. Since the thin-film single-crystal silicon obtained by this method is made by epitaxial growth on a high-quality single-crystal silicon substrate, the quality is extremely high. Further, in the step e), after the separation, the remaining portion of the porous layer on the substrate surface is removed and regenerated by means such as polishing or etching, and the regenerated substrate 308 can be reused in the step a). Since an expensive substrate can be used repeatedly in this manner, the manufacturing cost can be significantly reduced.

The peeling step among all the steps greatly affects the quality of the thin film single crystal, the production throughput and the yield, and will be described in detail with reference to FIG. In this figure, a release layer 202 is formed on a substrate 201. This is a layer that can be cut by applying an appropriate force from the outside, and corresponds to the porous layer 302 in the step of FIG. A thin film single crystal 203 is formed thereon. In order to efficiently remove the thin film single crystal 203, it is preferable to use the method shown in FIGS. Here, a flexible sheet member (flat member) 204 is attached to the surface of the thin film single crystal 203.

Although the sheet member 204 is drawn directly on the thin-film single crystal 203 here, an anti-reflection layer, an electrode, etc., are formed on the thin-film single crystal 203 as in the process shown in FIG. The sheet member 2 having the additional layer formed thereon
04 may be pasted. When the device is a solar cell and light enters from the surface as in the process of FIG. 3, the sheet member 204 or an adhesive for attaching the sheet member 204 is transparent or can be peeled off later. Must be. Light can also enter from the separation layer 202 side of the thin film single crystal 203. In this case, the sheet member 204 may be opaque, but is preferably conductive, and a metal sheet or the like is preferably used. In this state, the end portion of the sheet member 204 is held to the peeling roller 205 and a rotational force is applied to the peeling roller 205, so that the peeling layer 20
2 is cut, and the thin film single crystal 203 gradually peels off from the edge of the substrate 201. This method is suitable for mass production of solar cells because the thin film single crystal 203 can be efficiently separated.

However, the thin film single crystal 2
When the film 03 was peeled off, the thin film single crystal 203 often had minute defects or, in severe cases, cracks 209 as shown in FIGS. 2a) and 2c). In order to prevent the occurrence of defects and cracks, it is possible to take measures such as reducing the strength of the peeling layer 202 and increasing the radius of the peeling roller 205. However, in the former measure, the thin film single crystal 203 is subjected to a peeling process. There is a risk that the film will be peeled off before entering, and the latter measure may not provide a sufficient peeling force. In order to solve this problem, the present inventors have investigated the situation where the thin film single crystal silicon is cracked when peeling using various silicon wafers, and obtained the results shown in Table 1.

[0015]

[Table 1] 面 Surface of wafer used Main direction of cracking ──────── ｛{100} <110> ｛110｝ <112>, <110> ｛111───────── <110> ───────── ────────────────── Here, the direction of the crystal is expressed as <100>, which is
[100] represented by the symmetry of the crystal structure
In general, a direction equivalent to
It is represented as 0 °, which is represented by (100), and represents a plane orientation equivalent to (100) depending on the symmetry of the crystal structure. From the results in Table 1, it can be seen that the direction in which cracks enter the thin-film single-crystal silicon coincides with the direction in the thin-film surface corresponding to the surface of each wafer used as the substrate that is known to be most easily cleaved. all right. Further, even in the case of peeling from the same substrate in some cases, there were cases where cracks were easily formed and cases where cracks were hardly formed. I knew I was doing it.

That is, in FIG. 2, when the forefront 207 where the peeling is progressing coincides with the direction in which the cleavage is likely to occur, there is a tendency that cracks are remarkably formed. In this case, the substrate 201 has a plane orientation of {100}, the orientation flat 206 faces <110>, and the forefront 207 of the peeling is in a direction <110> where cleavage is likely to occur.
It seems that cracks were easy to be formed because it was parallel to>.
An improvement in this point is the peeling method shown in FIG. 1, in which the forefront 107 of the peeling is intentionally shifted from <110>, and in this case, almost no cracks were formed. A similar tendency is seen when substrates with other plane orientations are used,
An experiment was conducted by changing the angle between the forefront 107 of peeling and the azimuth in the substrate surface where cleavage was most likely to occur. When the angle was 5 degrees or more, the cracking was clearly reduced.
Above 0 degrees, almost no cracks were formed.

This result can be further generalized. That is, in the case of a crystal having a diamond structure shown in FIG. 4 such as silicon, cleavage tends to occur on the {111} plane. Therefore, even if the surface of the wafer has any orientation, the direction in which the {111} plane appears on the surface of the wafer is the direction in which the crack is likely to enter. Can be suppressed. 4 to 6 show examples of directions in which cracks easily occur in a wafer having a general plane orientation. FIG. 4 shows a unit cell of a crystal having a diamond structure. In FIG. 4, 407 represents a {111} plane,
This is the most easily cleaved surface of a diamond-structured crystal. Reference numeral 405 denotes a {100} plane. When the crystal is cut on this plane, the {111} plane 407 appears as a straight line oriented in the <110> direction as indicated by 408. However, <1
10> has a plurality of equivalent objects, and 408 shows two types of straight lines, all of which are represented as <110>.

FIG. 5A is a front view of the wafer 501 cut at {100}, and 503 indicates the direction of <110>. According to the knowledge of the present inventors, the direction of the forefront of peeling should be inclined at least 5 degrees, preferably at least 10 degrees from this direction. However, since there are two equivalent directions in <110>, a desirable direction is finally indicated by 504. In FIG. 4, reference numeral 406 denotes a {111} plane equivalent to 407. When the crystal is cut on this plane, the {111} plane 40
6 appears as a straight line directed in the <110> direction as indicated by 409. However, <110> has a plurality of equivalent
09 shows three types of straight lines, all of which are <11.
0>.

FIG. 5B is a front view of the wafer 505 cut at {111}, and 507 indicates the <110> direction. In this case, the desired direction is as shown at 508.

Further, the above concept can be applied to the case where a thin film single crystal having a crystal structure other than the diamond structure is peeled off. For example, III-V semiconductors such as GaAs and InP, ZnS
In the case of a semiconductor having a zinc-blende type structure such as II-VI semiconductors such as e and InS, it is said that the [110] plane is most easily cleaved. What is necessary is just to shift the angle of the forefront of peeling from the appearing direction.

FIG. 6 is a front view of a zinc-blende type semiconductor wafer 601 cut at {100}.
3 indicates the direction of <100>. In this case, the desired direction is as shown at 604.

[0022]

The following examples of the present invention will be described.

Embodiment 1 In this embodiment, the present invention is applied to the manufacture of the thin-film single-crystal silicon solar cell shown in FIG. Plane orientation ｛11
A 1｝ p ⁺ silicon wafer 301 is mixed with a mixture of hydrofluoric acid and isopropyl alcohol (a mixture of 49% by weight of hydrofluoric acid (the remainder being water) and 99.9% of pure isopropyl alcohol; volume ratio 1: 0.1). Immersed in the wafer 30
Anodization was performed using No. 1 as a positive electrode and a platinum plate as a negative electrode. When a current was applied at a current density of 1 A / cm ² for 5 minutes, about 5 μm from the surface
Fine pores intricately entangled up to a depth of m were formed, and the porous layer 302 was formed. On the surface of the porous layer 302, in a liquid phase growth apparatus using a melt prepared by dissolving p-type silicon in indium as a solvent,
A p-type thin film single crystal silicon layer 303 having a thickness of about 30 μm was epitaxially grown.

The epitaxial growth of the silicon layer 303 was confirmed by an electron diffraction method. Further, the fact that the thin film single crystal 303 is p-type was confirmed by measuring the Hall effect of the thin film single crystal peeled by the method of the present invention in this state. On a surface of the p-type thin film single crystal silicon layer 303, a liquid phase growth apparatus using a melt prepared by dissolving n ⁺ -type silicon in tin using tin as a solvent was used to have a thickness of about 0.
A 2 μm n ⁺ type thin film single crystal silicon layer 304 was epitaxially grown. By sputtering on this surface,
A layer of silicon nitride having a thickness of about 70 nm was deposited as the anti-reflection layer 305. A through hole was formed on this surface, and a grid electrode 306 was formed by printing. On top of that, a sheet member 104 as shown in FIG.
Was adhered using EVA as an adhesive layer (not shown).

The end of the sheet member was held by a peeling roller 105 having a diameter of 100 mm and wound up from the periphery.
At this time, the position where the sheet member is added, the peeling roller 105
Note that the direction of this axis is always 4 degrees with the wafer orientation flat (orientation is <110>) 106.
Winded up to make an angle of 5 degrees. At the same time, the thin film single crystal silicon began to peel off from the porous layer 302.
At that time, the direction of the front line 107 where the peeling occurred was parallel to the direction of the axis of the peeling roller 105. When the winding was continued as it was, the entire thin film single crystal silicon was peeled off from the substrate.

A back electrode 307 of a stainless steel plate was adhered to the back surface using a conductive adhesive containing copper as a main component.
In this state, when a measurement was performed using a solar simulator adjusted to AM1.5, a conversion efficiency of 15% was obtained. The conversion efficiency of this solar cell was 14.0% in an environment of a temperature of 45 ° C. and a humidity of 85%, which was a value enough for practical use. Next, when the peeled wafer is immersed in a nitric acid-based etching solution, the remaining portion of the porous layer remaining on the surface of the wafer is dissolved away, and the surface of the regenerated substrate (wafer) 308 has a mirror surface. became. The solar cell obtained by repeating the above process using this wafer also has a conversion efficiency of 1
4.8%, indicating that the wafer could be used repeatedly.

On the other hand, when the thin film single crystal was peeled off, a solar cell was prototyped in exactly the same manner as described above except that the axis of the peeling roller was wound up parallel to the orientation flat. And the disconnection of the grid electrode was observed. The conversion efficiency of this solar cell is 4.5%, and the temperature is 45 ° C. and the humidity is 8
At 5%, no output was obtained. Further, a single crystal layer remained in a flake shape on the wafer after peeling, and a clean surface could not be obtained by etching. In addition, when the film was wound up so that the direction of the axis of the peeling roller and the direction of the orientation flat 106 of the wafer were always at an angle of 5 degrees, it did not seem that cracks appeared at first glance, and the conversion efficiency was 14.5. %, Which is a performance that can withstand practical use. However, in an environment where the temperature is 45 ° C and the humidity is 85%, the conversion efficiency is 5.
It was significantly reduced to 5%. It is considered that a minute defect that is difficult to observe has occurred. Such a remarkable decrease in performance due to high temperature and high humidity was not observed when the direction of the axis of the peeling roller and the direction of the orientation flat 106 were constantly wound so as to form an angle of 10 degrees.

Embodiment 2 In this embodiment, the present invention is applied to the manufacture of a solar cell using thin-film single crystal gallium arsenide (GaAs). A p-type GaAs wafer having a plane orientation of {100} was prepared. An n ⁺ -type GaAs having a thickness of 0.1 μm was epitaxially grown on a surface of the substrate by a liquid phase growth apparatus using a melt in which gallium was used as a solvent and arsenic and a small amount of silicon were dissolved therein. Thereafter, hydrogen ions are applied to the surface of the wafer at an accelerating voltage of 500
5 × 10 ¹⁶ / cm ^{2 was} implanted at keV. Thereafter, a silicon nitride layer having a thickness of 70 nm was formed as an antireflection layer on this surface. At that time, the substrate temperature was set to 450 ° C. After forming a through hole on this surface, a grid electrode was formed by printing. A sheet member 10 as shown in FIG.
A polycarbonate film having a thickness of 0.3 mm as No. 4 was attached as an adhesive layer (not shown) using an acrylic adhesive.

The end of the sheet member was held by a peeling roller 105 having a diameter of 100 mm and wound up from the periphery. At this time, the position for holding the sheet member, the peeling roller 1
Paying attention to the direction of the axis 05, the film was rolled up so that the direction of this axis always forms an angle of 45 degrees with the wafer orientation flat (direction: <100>) 106. At the same time, peeling started at a portion of 5 μm from the surface of the single crystal GaAs wafer.
This is because hydrogen ions are implanted from the surface, and the hydrogen ions are concentrated at a depth of 5 μm from the surface and aggregate during the sputtering of silicon nitride to apply stress to the crystal structure and form a peeling layer. Therefore, it is considered that when an external force was further applied thereto, it was separated from this portion. The direction of the front line 107 where the peeling occurred was parallel to the direction of the axis of the peeling roller 105.

When the winding was continued as it was, a single crystal
The thin-film single crystal GaAs in which a portion of 5 μm from the surface of the GaAs wafer and the GaAs epitaxial growth layer were laminated was peeled off from the substrate. A back electrode of a stainless steel plate was attached to the back surface using a conductive adhesive mainly containing copper. In this state, when a measurement was performed using a solar simulator adjusted to AM1.5, a conversion efficiency of 18% was obtained. Next, when the peeled wafer was immersed in a nitric acid-based etching solution, the surface of the wafer became a mirror surface. A solar cell obtained by repeating the above steps using this wafer also showed a conversion efficiency of 17.5%, indicating that the wafer could be used repeatedly.

On the other hand, when the thin film single crystal was peeled off, a solar cell was prototyped in exactly the same manner as described above except that the axis of the peeling roller was wound up so as to be parallel to the orientation flat. And the disconnection of the grid electrode was observed. In addition, a single-crystal layer remained in a flake shape on the wafer after peeling, and a clean surface could not be obtained by etching.

Embodiment 3 In this embodiment, the present invention is applied to the manufacture of a member for an image display element in which a thin film single crystal for forming a light-transmitting drive circuit is attached to quartz glass.

A p ⁺ silicon wafer having a plane orientation of {100} is mixed with a mixture of hydrofluoric acid and isopropyl alcohol (49% by weight).
The mixture was immersed in a mixed solution of hydrofluoric acid (the remainder being water) and isopropyl alcohol having a purity of 99.9%; volume ratio 1: 0.1), and the wafer was subjected to anodization using a positive electrode and a platinum plate as a negative electrode. When current was applied at a current density of 1 A / cm ² for 5 minutes, a porous layer was formed from the surface to a depth of about 5 μm. There, fine holes that were complicatedly involved were formed. On the surface of the porous layer, a p-type thin film single crystal silicon layer having a thickness of about 0.5 μm was epitaxially grown by thermal CVD using trichlorosilane (SiHCl ₃ ) at a substrate temperature of 1000 ° C. After that, the surface of the thin film single crystal was sufficiently washed, and a flexible quartz glass supporting plate (sheet member) having a hydrophilic surface was bonded to the washed surface and heated. Strongly adsorbed.

Thereafter, the thin film single crystal was separated from the silicon wafer by the method shown in FIG. In FIG. 7, the silicon wafer is shown as a substrate 701. The back surface of the wafer is strongly attracted to the table by a method such as vacuum suction or electromagnetic suction. In this state, the separation wedge 70 is from the left.
4 was inserted. In order to create a trigger for insertion, the tip of the thin film single crystal 702 may be removed (705), or a tapered portion 706 may be formed at the tip of the quartz glass support plate 703. When the wedge 704 enters, the thin film single crystal 70
2 and the wafer 701 began to peel off at the porous layer (not shown) at the interface. At this time, the forefront 707 of the separation was set at 45 ° with respect to the {110} direction of the wafer.

The thin film single crystal thus peeled off was etched at 1050 ° C. in a hydrogen atmosphere after removing the remaining portion of the porous layer on the surface by etching. As a result, the surface became almost completely flat. This thin film is almost a perfect single crystal layer, but has a thickness of only 0.5μm. Therefore, unnecessary parts can be easily removed after the circuit is built, and light transmittance can be achieved. It is suitable for producing. In addition, since the wafer can be reclaimed and used repeatedly, the production cost can be reduced.

On the other hand, when the forefront 707 of separation was aligned with the {110} direction, the surface of the separated thin film single crystal was {1}.
Streaky irregularities extending in the direction of 10 ° were observed, and a good surface could not be obtained even after hydrogen annealing.

[0037]

As described above, according to the method of the present invention, a thin film single crystal can be repeatedly peeled from a substrate while maintaining high quality, and a driving circuit for a high-performance solar cell or liquid crystal display element can be obtained. Can be manufactured at low cost and with good yield.

[Brief description of the drawings]

FIG. 1 is a drawing showing the concept of a peeling process.

FIG. 2 is a drawing showing the concept of a peeling step.

FIG. 3 is a process diagram showing a process of manufacturing a thin-film single-crystal silicon solar cell using a porous layer.

FIG. 4 is a drawing showing a unit cell of a crystal having a diamond structure.

FIG. 5 is a front view of a wafer obtained by cutting a crystal having a diamond structure, a) is a front view of a wafer cut to {100}, and b) is a front view of a wafer cut to {111}.

FIG. 6 is a front view of a wafer obtained by cutting a crystal having a sphalerite structure at {100}.

FIG. 7 is a view showing the concept of a step of separating a thin film single crystal with a quartz glass support plate from a silicon wafer.

[Explanation of symbols]

 101, 201, 301, 701 Substrate 102, 202 Release layer 103, 203, 702 Thin film single crystal 104, 204 Sheet member 105, 205 Release roller 107, 207, 707 Forefront of peeling 209 Crack 302 Porous layer 303 First single Crystal layer 304 Second single crystal layer 305 Antireflection layer 703 Quartz glass support plate 704 Separation wedge 705 Tip removal section 706 Taper section

Continuation of the front page (72) Inventor Iwa ▲ saki ▼ Yukiko 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Takao Yonehara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Kiyofumi Sakaguchi 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Noritaka Uchiyo 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. F Terms (reference) 4G077 AA03 BA04 FJ03 5F051 AA02 BA05 BA15 BA17 GA04 GA05 GA06 GA20

Claims (8)

[Claims] An exfoliation layer and a thin film single crystal are formed in this order on a surface of a substrate, and are formed on the surface of the thin film single crystal or a layer additionally formed on the surface of the thin film single crystal. A thin sheet single crystal device is attached by attaching a flexible sheet member, further applying a force to bend the sheet member, separating the thin film single crystal from the substrate together with the sheet member, and using the thin film single crystal. In the method of manufacturing, when peeling the thin film single crystal from the substrate, the direction of all the straight lines and the direction of the forefront of peeling the most easily cleaved surface of the thin film single crystal appears on the surface of the thin film A method of manufacturing a thin-film single-crystal device, characterized in that the thin-film single-crystal is peeled off so that the two do not match. 2. The method for manufacturing a thin film single crystal device according to claim 1, wherein the forefront of the separation forms an angle of 5 degrees or more with the straight line. 3. The method for manufacturing a thin film single crystal device according to claim 1, wherein the forefront of the separation forms an angle of 10 degrees or more with the straight line. 4. The method for manufacturing a thin film single crystal device according to claim 1, wherein the crystal structure of the thin film single crystal is a diamond type. 5. The method for manufacturing a thin film single crystal device according to claim 1, wherein the crystal structure of the thin film single crystal is a zinc-blende type. 6. The substrate is a single crystal wafer, the release layer is a porous layer formed on a surface of the single crystal wafer,
The method for manufacturing a thin film single crystal device according to claim 1, wherein the thin film single crystal is a thin film epitaxially grown on a surface of a porous layer. 7. The method for manufacturing a thin film single crystal device according to claim 1, wherein said thin film single crystal device is a solar cell. 8. The method for manufacturing a thin film single crystal device according to claim 1, wherein said thin film single crystal device is an image display element driving circuit member.