JPH02187077A - Flexible photoelectric conversion element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to a visible charge conversion element, and in particular to a flexible photoelectric conversion element that uses a transparent polymer film as a substrate and receives light from the substrate side. It is related to.

(b) Conventional Technology Solar cells, optical sensors, and the like are widely used as photoelectric conversion elements that output electricity by irradiating light.

In a solar cell, a p-type crystalline silicon layer, an i-type crystalline silicon layer, an n-type crystalline silicon layer, and an
An amorphous silicon-based semiconductor layer formed by sequentially depositing crystalline silicon layers in the form of thin films, and a transparent electrode layer laminated on this amorphous silicon layer, or a substrate made of a glass plate. a transparent electrode layer, a p-type crystalline silicon layer, i
In practical use, an amorphous silicon-based semiconductor layer is formed by sequentially depositing a crystalline silicon layer and an n-type crystalline silicon layer, and a metal back electrode layer is further laminated on this amorphous silicon layer. has been made into

The substrate that also serves as the back electrode layer is formed of a metal foil or thin plate such as stainless steel or aluminum, and the transparent electrode layer is formed of, for example, tin oxide, indium oxide, or tin oxide-indium oxide (hereinafter referred to as ITO). Abbreviation) formed by h4.

In the former case, which uses metal substrates, the electric resistance of the substrates is sufficiently low, so it is suitable for obtaining a large current from two substrates.

In addition, in the latter case where a glass plate is used as a substrate, since the substrate has electrical insulation properties, it is easy to obtain more than twice the voltage by arranging multiple semiconductors adjacent to each other and connecting them in series. It is.

By the way, there are many products using such amorphous silicon-based semiconductors! Batteries (called amorphous silicon solar cells), etc., are currently being manufactured by reducing material costs, making them lighter and thinner, and making them easier to handle during the production process or transportation. In order to reduce costs, transportation costs, etc., it has been proposed to use a visible substrate.

For example, a heat-resistant plastic film such as a polyimide film is used as a substrate, and a metal electrode layer such as a stainless steel foil or film and an amorphous silicon semiconductor layer are formed on this substrate.
Laminated transparent electrode layers have been proposed (for example, JP-A-54-149489, JP-A-55-49).
No. 94, JP-A-55-29154, JP-A-Sho. 5
7-103839, etc.).

This type of amorphous silicon solar cell is lightweight, thin,
In addition, since the material cost is low (and it is highly flexible), it is possible to reduce production costs or transportation costs by winding it into a roll and processing it continuously, which is very advantageous.

However, the polyimide film used as a substrate does not have sufficient transmittance for visible light such as sunlight, so after forming a metal thin film (back electrode) on this film as described above, a semiconductor layer such as amorphous silicon is applied. A solar cell is manufactured by depositing a transparent electrode layer such as ITO on top of the deposit. That is, the light is incident on the opposite side of the substrate.

Usually, considering the influence of autodoping on the i-layer,
Back side 1 where a p-layer with relatively little influence is fabricated on the substrate!
After forming on the clay, amorphous silicon layers are deposited in the order of i-layer and n-layer, and a transparent electrode layer is further formed to complete the solar cell.

This order of deposition of the amorphous silicon layer is advantageous when using an optically transparent substrate such as glass, but it is advantageous when using an optically non-transparent substrate such as on the opposite side of the substrate (i.e. n There is a problem in the case of a type that allows light to enter from the layer side). When irradiating light onto the p-layer or n-layer surface, each p-layer or one
Many electrons and holes are generated near the layer.

By the way, compared to electrons, the lifetime and mobility of the genuine card are small, so when light is incident from the nNJ side, holes with short lifetimes and mobility need to travel a long distance to reach the p layer. Because of this, the photoelectric conversion efficiency is poor.

For the above-mentioned reasons, depositing +Jl, il, and p layer 1 in this order is problematic; therefore, generally, a light-transmissive substrate is used, and p-layer, iNJ, and n-layer are deposited in this order from the substrate side. A type that allows light to enter from the substrate side is advantageous.

Therefore, several proposals have been made regarding amorphous silicon solar cells using a visible and light-transmissive polymer film as a substrate (for example,
194582, JP 61-168271, JP 62-36882, etc.).

All of these applications use heat-resistant polymer films to withstand the deposition temperature of amorphous silicon. By the way, these heat-resistant polymer films have excellent heat resistance, but the polymer film substrate has a larger coefficient of thermal expansion than the amorphous silicon layer, so it is difficult to place an amorphous layer on the polymer film substrate. When the quality silicon layer is returned to room temperature after deposition,
A noticeable curl occurs with the substrate facing inside.

As a measure to prevent this curl, the present applicant has developed a flexible and electrically insulating substrate made of transparent plastic, a transparent electrode layer and a semiconductor layer laminated on the substrate, and a back electrode layer formed on the upper surface of the substrate. Furthermore, we have already proposed a flexible light-receiving element with a sandwich structure consisting of a flexible electrical insulating layer laminated on the upper surface of this substrate and having heat shrinkage characteristics equivalent to that of the above-mentioned substrate (Japanese Patent Application No. 63-34660; day 63 year 2
16th of the month).

(e) Problems to be Solved by the Invention Although this visible photoelectric conversion element is very effective as a measure to prevent the occurrence of curling, it does not satisfy only the essential conditions of the charging conversion element of the present invention; Countermeasures require material and process costs, and a simpler structure is desired.

(d) Means for Solving the Problems As a result of intensive study from point a, the present inventors found that a transparent polymer film was used as a light-transmissive substrate, and silicon dioxide was added to one side of the polymer film. , silicon nitride, silicon oxynitride, tetramethoxysilane condensate, tetraethoxysilane condensate and monomethyltriethoxysilane condensate, transparent conductive film, etc. are formed, and this thin film allows the high-temperature environment during amorphous silicon deposition to be formed. It protects the underlying substrate made of transparent polymer film, reduces curling due to shrinkage of the substrate film when taken out to room temperature after depositing amorphous silicon, and uses flexible photoelectric conversion elements. It protects the surface of the transparent polymer film substrate that is used as a window material at the time, greatly improving its abrasion resistance, and also prevents reflection of incident light by considering the combination with the refractive index of the substrate film. The present invention has been completed based on the discovery that this method is possible, and that the photoelectric conversion efficiency and other characteristics are also extremely good, making it suitable for practical use.

Although this flexible photoelectric conversion element has a very slight curl with the substrate inside, it has sufficient practicality as it is without any reinforcement.

The present invention will be explained in detail below.

In the present invention, the visible photoelectric conversion element refers to a light receiving element that inputs light and outputs electricity, and includes all flexible elements. Specifically, it includes photoconductive elements, photodiodes, Examples include solar cells, e)) transistors, and photothyristors. Moreover, here, the color light includes not only visible light but also infrared light and the like.

Hereinafter, first, the visible charge conversion element of claim 1 will be explained in detail.

That is, this flexible photoelectric conversion element includes a substrate made of a transparent polymer film, a thin film of silicon dioxide formed on one side of the substrate, a transparent conductive film formed on the side opposite to the side on which this thin film is formed, and a silicon dioxide thin film formed on one side of the substrate. It consists of an amorphous silicon-based semiconductor layer formed on a transparent conductive film, and a back electrode layer formed on the amorphous silicon-based semiconductor.

The substrate made of transparent polymer film used in the present invention is not particularly limited as long as it is transparent, has heat resistance, flexibility, and electrical insulation. Specific representative examples of transparent polymer films include polyethylene terephthalate, polyethylene naphthalate, polyimide, polyether sal 7,
Films formed from polysulfone, polyetherimide, 4-methylpentene terephthalate, etc. can be listed.

In this transparent substrate, it is desirable that the visible light M (550 nm) transmittance per 100±5 μm thickness is 60% or more.

In the present invention, a silicon dioxide film is formed on one side of the transparent polymer film substrate.

This thin film protects the transparent polymer film substrate in the high-temperature environment during amorphous silicon deposition, and prevents curling due to shrinkage of the substrate film when it is taken out to room temperature after amorphous silicon deposition. In addition, it protects the surface of the transparent polymer film substrate used as a window material when using visible photoelectric conversion elements, extremely improving friction resistance, and further improves the refractive index of the substrate film. By considering the combination, it is possible to prevent the reflection of incident light, and the properties such as photoelectric conversion efficiency are also extremely good, making it fully practical.

Although the flexible photoelectric conversion element formed with this thin film curls only slightly with the substrate inside, it does not require any reinforcement and has sufficient practical use as it is.

The film thickness of silicon dioxide is generally 30 to 1100.
It is preferable that the thickness be in the range of 0n, especially in the range of 1100-500n; if this thickness is less than 30n11, it will not be possible to protect the substrate during deposition of the amorphous silicon semiconductor, and it will not be possible to prevent the occurrence of curling. Also, it is not preferred because the desired abrasion resistance cannot be obtained, and on the other hand, 110
If it exceeds 00n, it becomes too thick and causes a problem with the flexibility of the flexible charge conversion element, which is not desirable.

In the present invention, silicon dioxide refers to silicon dioxide having a refractive index in the range of 1.4 or more and less than 1.5 as measured by an ellipsometer.

The method of forming this silicon dioxide thin film is not particularly limited, and examples thereof include sputtering and electronic R-evaporation.

Then, in the substrate with the silicon dioxide thin film, a transparent conductive film is formed on the side opposite to the side on which the silicon dioxide thin film is formed.This formation method includes forming a transparent electrode layer on the substrate by sputtering, vapor deposition, It is formed by a method such as printing.

The thickness of this transparent electrode film is not particularly limited, but specifically, it is about 50 to 3000, especially considering the balance between discoloration resistance and visible light transmittance.
The area around 1,000 to 1,000 people appears to be discolored.

If the thickness of the transparent electrode film is less than 50, it is not preferable because the thickness becomes too thin and the desired conductivity (surface resistance of 1000 Ω/mouth or less) cannot be obtained.
If it exceeds 0OA, the thickness becomes too thick and the transparency of the transparent electrode film may decrease, which is not preferable.

In addition, when forming multiple cells on one substrate,
For example, unnecessary portions of the transparent electrode film are removed by a technique such as 7-OF etching.

This transparent electrode film may be made of a known material (
Examples include a film formed of tin oxide, indium oxide, or a solid solution of both (ITO).

In the present invention, an amorphous silicon-based semiconductor layer having photovoltaic properties is formed on the transparent electrode film.

The amorphous silicon-based semiconductor layer is not particularly limited as long as it has photovoltaic properties, and examples include amorphous silicon for visible light.

For example, when forming a semiconductor layer with silicon, it is possible to form a p-n junction by diffusing active impurities into single crystal silicon, but it is also possible to form a p-n junction by diffusing active impurities into single crystal silicon. It is advantageous to sequentially deposit the crystalline silicon layer and the n-type crystalline silicon layer in order to reduce the thickness of the semiconductor layer.

In addition, a p-type valvous crystalline silicon layer, an i-type valvous crystalline silicon layer and a V
As a method for sequentially depositing the n-type amorphous silicon layer, various methods such as sputtering method, glow discharge method, photo-CVD method, and ion-blating method can be employed.

For example, if we take the case of employing the glow discharge method as an example and explain it specifically, the temperature will be around 200℃ (150~280℃).
) The substrate with the transparent electrode formed thereon was held in a holder heated to
5*000ppm with silane and hydrogen diluted to about mol%
Diporan mixture diluted to a certain degree [BzHa/(SiH
++B2)111)=0. 1 to 0.6 mol %, preferably about 0.3 mol % 1 is injected in a combined filoO 3 ccM, and in that atmosphere, the holder is used as one electrode, and a counter electrode is connected at 13.56 MHz, 10
A p-type crystalline silicon layer doped with boron is formed on the transparent electrode layer to a thickness of 100 to 5.
00 people, especially about 200 people, will be discolored.

Subsequently, only hydrogen diluted silane was supplied at a total flow rate of 11003C.
Under the atmosphere introduced in step C, a non-doped i-type crystalline silicon layer was deposited to a thickness of 2,500 to 7,000 layers, particularly about 4,500 layers, in the same manner as above, and further diluted with hydrogen to a concentration of 5,000 ppm using silane and hydrogen. Diluted 7-osufine (P
) I 3) mixture [PH3/ (S iH4+ P
H3) = 0, 1-0.6 mol%, preferably 0
．． 3 mol %] was introduced at a confluence of 1100 sccm, an n-type crystalline silicon layer doped with phosphorus was similarly deposited to a thickness of 250 to 1000 layers, particularly about 500 layers.

By the way, for convenience, the explanation has been given using p-1-n type amorphous silicon as a photovoltaic element, but in addition to amorphous silicon, the 9th layer contains ρ-type amorphous silicon carbide (film composition: 5ixC, −
Indicated by x, x=0.6 to 0.95, preferably x=0
．． A film doped with Ciborane 82H, etc.) can also be used.

In this case, the carbonization source used is a saturated hydrocarbon such as methane or ethane, or an unsaturated hydrocarbon such as ethylene or propylene.

The molar ratio of silane (S iH, ) or disilane (Si2Hs) used as a raw material and the above-mentioned hydrocarbons is determined as follows.

That is, for example, to produce a film with a film composition of S j Os 8 COs 2, the molar ratio of 5iH= and CH is 0.8:0.
2 (also 0.4 vs. 0.2 for 5izH- and CH4), S
i H< and C2Ha are 0.8 vs. 0, 1.5I2H@
and C2H, the ratio of Si in the raw material is 0.4 to 0.1.
The molar ratio is determined from the number of atoms and the number of C atoms.

In the present invention, a back electrode layer is further laminated on the amorphous silicon-based semiconductor layer.

This back electrode layer may be made of tin oxide, indium oxide, or a solid solution of both (ITO), like the transparent electrode layer stacked between the substrate and the amorphous silicon-based semiconductor layer. Also, aluminum, nickel, titanium,
It may be made of metal such as chromium, iron, stainless steel, nickel chromium, etc.

In this case, the back electrode layer is formed by a method such as a printing method, a sputtering method, or an evaporation method.For example, in the case of an evaporation method, the temperature of the evaporation source is 10-4 to ITorr in a vacuum. This is done under conditions near the melting point of the material.

The thickness of this back electrode layer is not particularly limited, but it must be at least thick enough to have the required conductivity without significantly reducing the flexibility of the entire visible light Wl conversion cord. For example, in the case of an aluminum electrode, 0.
Approximately 1 to 1.5 μI is considered appropriate.

In this way, in a substrate made of a transparent polymer film, a thin film of silicon dioxide is formed on one side of the substrate, a transparent electrode layer is formed on the side opposite to the side on which this thin film is formed, and p-type - 1-type - n-type An amorphous silicon-based flexible photoelectric conversion element in which an amorphous silicon-based semiconductor layer and a back electrode layer are laminated, in this case an amorphous silicon-based solar cell is formed.

In this way, the flexible photoelectric conversion element of the present invention is obtained.

Next, a flexible photoelectric conversion element according to a second aspect of the present invention will be explained.

That is, this visible photoelectric conversion element includes a substrate made of a transparent polymer film, a silicon dioxide thin film formed on both sides of the substrate, a transparent conductive film formed on one side of the thin film, and a transparent conductive film formed on the transparent conductive film. It consists of an amorphous silicon-based semiconductor layer formed on the amorphous silicon-based semiconductor layer, and a back electrode layer formed on the amorphous silicon-based semiconductor layer.

The invention of claim 2 relates to an improvement of the invention of claim 1, and its feature is that silicon dioxide is formed on both sides of the substrate made of a transparent polymer film. , the board can be more securely protected, -1fl
! A flexible photoelectric conversion element with improved characteristics can be obtained.

That is, it has a structure in which a transparent conductive film, an amorphous silicon semiconductor layer, and a back electrode layer are formed on one side of a substrate having silicon dioxide on both sides, but these are the same as claim 1. be.

Next, the visible photoelectric conversion element of claim 3 will be explained. That is, this visible photoelectric conversion element includes a substrate made of a transparent polymer film, a transparent conductive film formed on both sides of the substrate, and a transparent conductive film formed on both sides of the substrate. An i-film of silicon dioxide formed on one surface, an amorphous silicon semiconductor layer formed on the other surface of the transparent conductive film, and a back surface formed on the amorphous silicon semiconductor layer? It consists of a polar layer.

The visible charge conversion element according to claim 3 includes a substrate made of a transparent polymer film, a transparent conductive film formed on both sides of the substrate,
A structure in which a silicon dioxide thin film is formed on one side of the transparent conductive film, and an amorphous silicon-based semiconductor layer and a back electrode layer are formed on the transparent conductive film on the side opposite to the silicon dioxide thin film formation side. The formation of this silicon dioxide thin film prevents the occurrence of -layer curl, and provides a charge conversion element with -1 excellent characteristics.

Furthermore, a flexible photoelectric conversion element according to a fourth aspect of the present invention will be explained.

That is, in the above visible photoelectric conversion element, at least one selected from silicon nitride, silicon oxynitride, tetramethoxysilane condensate, tetraethoxysilane condensate, and monomethyltriethoxysilane condensate is used instead of the silicon dioxide thin film. It is made of a thin film.

Examples of methods for forming thin films of silicon nitride and silicon oxynitride include sputtering, electron beam evaporation, and the like. Thin films such as materials can be formed by applying the monomer or prepolymer using gravure coating or roller coating, followed by heat treatment.

In the above ri15K, the film thickness is in the range of 5O-500r+n, especially 1100-300
The range of n is preferably 200 to 200 for organic silicon compounds.
A range of 7,000 people, particularly a range of 800 to 4,500 people, is desirable.

If the thin film is too thin, the desired properties cannot be obtained;
If it is too thick, the overall flexibility will deteriorate, so either case is not preferable.

Furthermore, a flexible photoelectric conversion element according to claim 5 will be explained.

That is, in this visible photoelectric conversion element, the transparent polymer film is formed of a polyethylene terephthalate film or a polyethylene naphthalate film.

In this way, polyethylene terephthalate film (P
By using a polyethylene naphthalate film (referred to as E Because the coefficient of thermal expansion of the substrate is relatively low, the curl after forming the amorphous silicon thin film is small (and the resulting solar cell has a high photoelectric conversion efficiency due to the relatively high light transmittance of the substrate). Moreover, since the substrate has low hygroscopicity and dimensional change upon absorption of moisture is small, a visible photoelectric conversion element with good moisture resistance can be obtained.

In other words, although polyethylene terephthalate film or polyethylene naphthalate film can be expected to have many features in solar cells etc. as a substrate, it has traditionally been impossible to use due to low heat resistance. By forming such a thin film, it became possible to use such a film as a substrate.

(e) Effect The visible photoelectric conversion element of the present invention uses a transparent polymer film, and silicon dioxide, silicon nitride, silicon oxynitride, tetramethoxysilane condensate, or tetraethoxysilane condensate is applied to at least one side of the transparent polymer film. A thin film such as a monomethyltriethoxysilane condensate or a transparent conductive film is formed, and this thin film protects a substrate made of a transparent polymer film in a high-temperature environment during amorphous silicon deposition. Curling due to shrinkage of the substrate film when taken out to room temperature after deposition is significantly smaller, and
When using a flexible charge conversion element, the surface of the transparent polymer film substrate used as a window material is protected, and the abrasion resistance is extremely improved.Furthermore, by considering the combination with the refractive index of the substrate film, It is also possible to improve the light transmittance, and the characteristics such as charge conversion efficiency are also very good, and the effect is sufficient for practical use.

That is, if a film with a refractive index smaller than that of PET (refractive index 1.66) is attached, the transmittance from this direction increases. On the other hand, if a film with a refractive index greater than 1.66 is attached, the transmittance will decrease.

Also, this flexible photoelectric conversion element has a very slight curl with the substrate inside, but it is not reinforced (
, it has a sufficient practical effect as it is.

(f) Examples Hereinafter, the present invention will be explained in detail based on Examples, but the present invention is not limited thereto.

Example 1 A thin layer of silicon dioxide with a thickness of 90 nm was deposited on both sides of a PET film with a thickness of 100 μI by sputtering using a conventional method.
(refractive index 1.46), a 50 nm thick I
A TO film was formed.

The light transmittance of the obtained film at a wavelength of 550n was 84%.
Also, the sheet resistance of the ITO film was 50Ω/hole.

Next, this ITO film-coated film was held in an island holder with a heater in an internal electrode type high frequency (13,56MH2) glow discharge device, and the temperature was maintained at around 170°C.
Mix silane diluted to 10 mol% with hydrogen and diborane diluted with 100% methane and hydrogen to 5,0 Oppal [S iH4/ (S iH4+CH, +B, H,)
=80 mol%, CH4/ (S iH40C)14 +
82Hs) = 19, 7 mol%, B2H,/(S
iH4+CH4+B2H = 0.3 mol%], the total flow rate was introduced into a 11005 CC glow discharge device, and 10 W of high frequency power was applied in an atmosphere with a degree of vacuum of 0.2 Torr to dope boron onto the substrate. A 200 p-type crystalline silicon carbide layer was deposited.

Subsequently, only the above hydrogen-diluted silane was introduced, and a similar reaction was carried out to deposit a non-doped i-type valvus silicon thin film with a thickness of 4500 Å on the p-type valvate silicon carbide layer, and further hydrogen-diluted silane and Mix 7 osphin (PH3) diluted with hydrogen to 5.0OOpp jar [PH,/(
SiH, +PH, ) = 0.5 mol% 1, a total flow rate of 11008 CC was introduced into the glow discharge device, and a similar reaction was carried out to form 500 N-type valves doped with phosphorus on the type-1 valve crystalline silicon layer. A crystalline silicon thin film was formed.

That is, after forming a thin film of silicon dioxide (refractive index 1.46) on both sides of a PET film substrate, I
A photovoltaic amorphous silicon-based semiconductor layer consisting of p-type, i-type, and n-type amorphous silicon-based thin films was formed via a transparent conductive thin film of TO.

Next, this was held in a vacuum evaporation apparatus, and an aluminum back electrode layer having a thickness of 1 μm was laminated on the n-type crystalline silicon layer by a normal evaporation method.

The photoelectric conversion efficiency of the thus obtained visible photoelectric conversion element was measured using a solar simulator with AM=1.100 mW/am2, and was found to be 4.4%.

The obtained flexible photoelectric conversion element is slightly curved with a radius of curvature of about 50 cm+, with the film substrate side facing inside.
It had sufficient visibility and was flat under very slight tension, and no practical problems were observed.

Example 2 Using a PEN film with a thickness of 100 μm as a substrate, a film with a thickness of 200 nm was deposited on one side by sputtering using a conventional method.
After forming a silicon dioxide film, a 50 nm thick ITO film was formed on the opposite surface by sputtering using a conventional method.

The light transmittance of the obtained substrate with the ITO thin film at a wavelength of 550 nm was 86%, and the sheet resistance of the ITO film was 50Ω/hole.

Next, the same process as in Example 1 was carried out, and an amorphous silicon-based semiconductor layer and an aluminum back electrode layer were laminated on the side with ITOPX, thereby producing a flexible photoelectric conversion element.

As a result of conducting similar photoelectric conversion efficiency on the flexible photoelectric conversion element obtained in this way, the photoelectric conversion efficiency was 4.0
%, and the radius of curvature of the curve with the substrate inside is 30
It was about cm.

Example 3 Using the same PEN film as in Example 2 as a substrate, 1% ITO was formed on both sides in the same manner as in Example 2.

Next, this one side was subjected to the same treatment as in Example 1 to form a 90n-thick film of silicon dioxide (refractive index 1.46), and then the opposite side was subjected to the same treatment as in Example 1,
A visible photoelectric conversion element was fabricated.

As a result of conducting the same test as in Example 1 for this visible photoelectric conversion element, the charging conversion efficiency was 4.4%, and the radius of curvature was about 40cm.

Example 4 Silicon nitride (SisN<) was used as tarde on both sides of a PET film with a thickness of 100μ, and a pressure of 3X was applied.
10-' Torrs High voltage 2KV, frequency 111
Thickness: 30Onm by 3.56MHz high frequency sputtering
A thin film of silicon nitride was applied.

Next, a sheet resistance of 50 was applied to this one side as in Example 1.
After forming an ITO film of Ω/mm, an amorphous silicon-based semiconductor layer and an aluminum back electrode layer were further laminated on this side to produce a visible photoelectric conversion element.

The conversion efficiency of this photoelectric conversion element was 5.8%, and the curved radius of the own vehicle was 40 cm.

Example 5 The sputter target in Example 4 was
z (m composition: S : sN < 75 weight 1%, 5i0225
A visible charge conversion element was manufactured by carrying out the same process as in Example 4, except for using a compound (consisting of % by weight).

The second photoelectric conversion element had a conversion efficiency of 6.0% and a radius of curvature of 50 cm.

Example 6 A PEN film was used as the substrate in Example 5. A thin film of 5ixNyOz was attached to one side of the substrate, and the same treatment as in the example of Ike was performed on the opposite side to produce a flexible photoelectric conversion element.

The photoelectric conversion efficiency of this photoelectric conversion element was 4.2%, and the radius of curvature was 30 cm.

Example 7 Both sides of a 100 μ-thick PET film were gravure coated using an alcohol-based coating solution containing tetramethoxysilane (Si(OCH=)-) with a monomer concentration of 40% (by weight) (Oihe Kagaku Co., Ltd.). Coated with industrial product 5I-41), air-dried, and heated at 150°C for 2 minutes to a thickness of about 3000.
A methyl silicate condensation polymer film of nm size was formed. On one side of this, ITOII, an amorphous silicon-based semiconductor layer, and an aluminum back electrode layer similar to those in Example 1 were laminated to produce a flexible photoelectric conversion element.

The charge conversion efficiency of this photoelectric conversion element was 4.0%, and the radius of the curved float was 40 cm.

Example 8 A tetraethoxysilane (Si(OC285)-) based condensation polymer film was formed on both sides of a 100 μm thick PEN film in the same manner as in Example 6. Its thickness is 1000n
-It was.

One side of this was subjected to the same treatment as in Example 1 to produce a flexible photoelectric conversion element.

The photoelectric conversion efficiency of this photoelectric conversion element was 4.2%, and the radius of curvature of the surface was 30 cm.

Example 9 A monomethyltriethoxysilane (83CS i (OC2H5)t) based condensation polymer film was formed on both sides of a 100 μm thick PEN film. Its thickness was 30 On-.

This single side was subjected to the same treatment as in Example 1 to produce a flexible photoelectric conversion element.

The photoelectric conversion efficiency of this photoelectric conversion element was 3.6%, and the radius of surface curvature was 20 cm.

Comparative Example 1 Using a PET film with a thickness of 100 μI as a substrate, a photoelectric conversion element was produced as a prototype by performing the same process as in Example 1, without forming either a silicon compound-based WI film or a silicate ester-based condensation polymer. did. The obtained element was tightly curved within a radius of se1m of the vehicle with the film substrate facing inside, which caused a practical problem. Also, the photoelectric conversion efficiency is 1.8%.
It was observed that this was significantly lower than in other examples.

Comparative Example 2 Using a PEN film with a thickness of 100 μm as a substrate, a charging conversion element was prototyped in the same manner as in Comparative Example 1 by performing the same treatment as in Example 1 without performing any protection treatment on the substrate.

The obtained element was slightly curved (within a radius of curvature of 60111) with the film substrate inside, and it was recognized that there was a problem in practical use.

Furthermore, the photoelectric conversion efficiency was 1.9%, which was significantly lower than other examples.

Example 10 Using a PET film with a thickness of 100μ as a substrate, a 1000ni methyl silicate polymer film was formed on both sides in the same manner as shown in Example 6, and then a 100nm thick silicon dioxide film was formed by a conventional method. Formed. This single side was subjected to the same treatment as in Example 1 to produce a flexible photoelectric conversion element.

The photoelectric conversion efficiency of this photoelectric conversion element was 5.0%, and the radius of curvature was 40 cm.

The manufacturing conditions of the device and the characteristic results of the photoelectric conversion device are summarized in Table 1.

(Space below) Flexible photoelectric conversion of each of the above examples and comparative examples (g) Effects of the invention Since the present invention is configured as described above, it has the effects described below.

In the flexible photoelectric conversion element according to claim 1, WlI! of silicon dioxide is coated on one side of the substrate made of a transparent polymer film. 4 is formed, this thin film significantly reduces the curling of the substrate when it is taken out to room temperature after depositing amorphous silicon, and when using this flexible photoelectric conversion element, it can be used as a window material. It is effective for protecting the surface of polymer films and improving abrasion resistance, and also has extremely good properties such as photoelectric conversion efficiency, and has sufficient practical effects.

Furthermore, with this configuration, it is possible to prevent curling, and it also has the effect of reducing material costs and production costs.

In the flexible photoelectric conversion element of claim 2, thin films of silicon dioxide are formed on both sides of the substrate made of transparent polymer film, so that the substrate can be protected in a high temperature environment during deposition of amorphous silicon. This can be achieved more reliably and has the effect of having -1 superior characteristics.

In the visible photoelectric conversion element according to claim 3, a transparent conductive film is formed on both sides of the substrate made of a transparent polymer film, and a transparent conductive film is further formed on the transparent conductive film on the side opposite to the side on which the amorphous silicon semiconductor layer is formed. It is made of silicon dioxide, which has the effect of preventing layer curl from occurring and providing excellent properties.

In the flexible photoelectric conversion element of claim 4, by arbitrarily selecting the thin film to be formed on the substrate, it is possible to form a protective thin film with desired characteristics according to requirements. This has the effect of exhibiting the electrical characteristics of .

In the visible photoelectric conversion element according to claim 5, since a polyethylene terephthalate film or a polyethylene naphthalate film is used as the transparent polymer film that is the substrate, contamination due to bound water or adsorbed water is reduced, and there is no possibility of heat generation. In addition to having a small expansion coefficient and little curling, it also has good moisture resistance and excellent properties.

Claims (5)

[Claims] (1) A substrate made of a transparent polymer film, a thin film of silicon dioxide formed on one side of the substrate, a transparent conductive film formed on the side opposite to the side on which this thin film was formed, and a transparent conductive film formed on the transparent conductive film. A flexible photoelectric conversion element comprising an amorphous silicon-based semiconductor layer and a back electrode layer formed on the amorphous silicon-based semiconductor. (2) A substrate made of a transparent polymer film, a silicon dioxide thin film formed on both sides of the substrate, a transparent conductive film formed on one side of the thin film, and an amorphous film formed on the transparent conductive film. A flexible photoelectric conversion element comprising a silicon-based semiconductor layer and a back electrode layer formed on the amorphous silicon-based semiconductor. (3) A substrate made of a transparent polymer film, a transparent conductive film formed on both sides of the substrate, a silicon dioxide thin film formed on one side of the transparent conductive film on both sides, and a silicon dioxide thin film formed on the other side. A flexible photoelectric conversion element comprising an amorphous silicon-based semiconductor layer and a back electrode layer formed on the amorphous silicon-based semiconductor layer. (4) In the flexible photoelectric conversion element according to any one of claims 1 to 3, the silicon dioxide thin film is silicon nitride, silicon oxynitride, tetramethoxysilane condensate, tetraethoxysilane condensate, or monomethyltriethoxysilane condensate. A flexible photoelectric conversion element that is a thin film of at least one type selected from. (5) The flexible photoelectric conversion element according to any one of claims 1 to 4, wherein the transparent polymer film is a polyethylene terephthalate film or a polyethylene naphthalate film.