JP2002141532A - Method for manufacturing integrated photosensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method manufacturing an integrated photosensor which prevents short-circuiting between scribe lines to provide a good yield and a high reliability in a long use. SOLUTION: The method of manufacturing a plurality of integrated photosensors arranged on the same substrate, each composed of at least a lower electrode layer 103, a semiconductor layer 105 and an upper electrode 107, comprises a step of forming an insulation film 108 on the surface of the electrode layer or the semiconductor layer and a step of scribing at least the electrode layer or the semiconductor layer, starting from the insulation film 108.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a functional photovoltaic device used for a solar cell, a thin film transistor, and the like, and more particularly to a method of manufacturing an integrated photovoltaic device having a rectifying function. is there.

[0002]

2. Description of the Related Art Conventionally, in order to increase the output voltage of a photovoltaic element, an integrated photovoltaic element formed by dividing a photovoltaic element formed on the same substrate into a plurality of parts and connecting them in series is integrated. Power elements are known. As a method,
A technique of dividing a transparent conductive layer or a photoelectric conversion layer using a laser, that is, a laser scribe technique has been studied and many proposals have been made.

[0003] For example, Japanese Patent Application Laid-Open No. 5-25173 discloses that
A plurality of photoelectric converters comprising a substrate-side thin film electrode, an amorphous semiconductor formed of a pin junction formed on the thin film electrode, and a back thin film electrode formed on the amorphous semiconductor layer are formed on a glass substrate. Y is provided as a means for removing a part of the amorphous semiconductor layer in a manufacturing process of an integrated solar cell module provided and part of the photoelectric converter being connected in series.
A technique using an AG laser is disclosed.

Japanese Patent Application Laid-Open No. Hei 7-307482 discloses that a first electrode is provided on a substrate-side electrode separately formed on the same substrate.
Forming at least one stacked semiconductor layer in which a conductive semiconductor layer, an i-type semiconductor layer, and a second conductive semiconductor layer having a conductivity type opposite to that of the first conductive semiconductor layer are stacked; In a manufacturing process of an integrated solar cell in which a back electrode is formed on the divided semiconductor layer by dividing by a layer division separation groove, and a substrate side electrode and a back side electrode of the adjacent laminated semiconductor layer are connected, a laser is used. There is disclosed a technique for forming the divisional separation grooves by a scribe method.

Further, Japanese Patent Application Laid-Open No. 9-8337 discloses that
On a first electrode layer divided into a plurality of regions on a substrate, a plurality of semiconductor layers having connection openings formed on one of the first electrode layers over two first electrode layers are provided. A conductive layer is provided in a region other than the connection opening on the semiconductor layer, and is electrically connected to one of the first electrode layers via the connection opening on the conductor layer. In the manufacturing process of the integrated thin-film solar cell in which a plurality of unit elements composed of a region sandwiched by the second electrode layer and the other first electrode layer are connected in series by providing the second electrode layer in the A technique for fusing an electrode layer by a laser scribe method is disclosed.

Japanese Unexamined Patent Application Publication No. 9-36397 discloses a first electrode and a second electrode laminated on both surfaces of an amorphous silicon layer, and the second electrode is laminated in close contact with an insulating substrate. The second electrode of an adjacent power generation cell is insulated by an insulating groove, and the first electrode and the second electrode of the adjacent power generation cell are connected by a laser connection, and are provided adjacent to the laser connection. In a manufacturing process of an integrated solar cell in which a laser cutting portion cuts a first electrode of an adjacent power generation cell, a technique of cutting an electrode by a laser scribe method and connecting the electrode by a laser welding method is disclosed. ing.

Further, Japanese Patent Application Laid-Open Nos. 9-129903 and 9-129906 disclose a unit element comprising a first electrode layer, a first stack cell, a second stack cell, and a second electrode layer on a substrate. In a manufacturing process of an integrated thin film tandem solar cell in which a plurality of unit elements are formed and these plurality of unit elements are connected in series, a technique of fusing and dividing an electrode and / or a cell by a laser scribe method is disclosed.

Next, a typical configuration of an integrated photovoltaic element (thin film solar cell) will be described. FIG. 11 is a schematic diagram showing a cross-sectional structure of a conventional photovoltaic element, which is a structure of an integrated thin-film solar cell generally employed conventionally.

In FIG. 11, 101 is a translucent insulating substrate, 103 is a lower electrode layer, 105 is a semiconductor layer, 107
Denotes an upper electrode layer, 109 denotes an upper electrode dividing groove for dividing the upper electrode layer, and 104 denotes a dividing groove for dividing the lower electrode layer 103 and the semiconductor layer 105 (division of the semiconductor layer is not essential).

An upper electrode layer 107, a semiconductor layer 105 made of amorphous silicon or the like, and a lower electrode layer 103 are sequentially laminated, and unit elements adjacent to each other are connected in series via a connection portion provided in the semiconductor layer 105. ing. Since it is necessary to transmit light, the upper electrode layer 107 is usually made of tin oxide (SnO ₂ ) or zinc oxide (Zn oxide).
O), a transparent conductive film such as indium tin oxide (ITO) or the like, and a metal film such as aluminum (Al), silver (Ag), chromium (Cr) or the like is used as the lower electrode layer 103.

[0011] Such a conventional integrated thin-film solar cell,
It is manufactured by the following manufacturing method. Note that a laser is used as a scribe method.

As shown in FIG. 11, on a light-transmitting insulating substrate (for example, a glass substrate) 101, SnO ₂ , Zn
A transparent conductive film such as O or ITO is deposited as the upper electrode layer 107 by a sputtering method or the like, and the upper electrode layer 107 is separated corresponding to a power generation region by a laser scribe method for integration. Then, cleaning is performed to remove the fusing residue generated during laser scribing, and plasma C is removed.
An amorphous silicon semiconductor layer 105 having a pin junction structure (a p-layer and / or an n-layer can be made of microcrystal if necessary) 105 is deposited over the entire surface by the VD method.

Subsequently, after the semiconductor layer 105 is separated by a laser scribe method as in the case of the upper electrode layer 107, cleaning for removing the fusing residue is performed. Furthermore, A
A lower electrode layer 103 is formed by depositing metals such as l, Ag, and Cr in a single layer or multiple layers, and separated by a laser scribe method in the same manner as the upper electrode layer 107 to complete an integrated large-area solar cell. I do.

[0014]

However, when the photovoltaic elements formed on the same substrate by the above-described laser or other methods are divided and connected in series, the integration is performed as follows. Problems exist.

That is, when a material such as a metal layer, a semiconductor layer, and a transparent electrode layer is cut off at the time of cutting at the time of division processing by a laser or other methods, fine metal or semiconductor cut and adhered to the division groove. As a result, electrical insulation becomes insufficient, and good electrical durability cannot be obtained. In order to prevent such fine dust, cutting is generally performed while air blowing is performed. However, in the conventional method, dust is not completely removed and remains in the cut portion. The leakage current caused by the short-circuit state thus generated is proportional to the voltage generated between the upper electrode layer 107 and the lower electrode layer 103.

On the other hand, when the light is weak, the output current of the solar cell is small, but the output voltage does not decrease so much. Therefore, even when the light is weak, the leakage current does not decrease so much. Therefore, when the light is weak, there is a problem that the power loss due to the leakage current becomes relatively large.

Such a shunt problem at the scribe portion occurs particularly in a metal layer or a transparent conductive film having a low resistance, and is more difficult than a short circuit of the dividing groove made of a material having a relatively high resistance such as a semiconductor. The decrease in electromotive force is remarkable.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, an object of the present invention is to provide a method of manufacturing an integrated photovoltaic device having a good yield by preventing a short circuit in a scribe line and having high reliability in long-term use. And

[0019]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have formed an insulating film on a semiconductor layer or a metal layer (electrode layer) to be cut. It has been found that by performing division through a film, dust due to cutting prevents short-circuiting, and a highly reliable integrated photovoltaic element with good yield can be obtained. Further, as a dividing method, a method using a laser, a method using a sand blast, a method using an ultrasonic wave, and the like are suitably used, and it is possible to minimize conductive dust generated at the time of cutting and to make it easy to remove. The inventors have found that the above problems can be solved, and have completed the present invention.

That is, the present invention provides at least a lower electrode layer,
A method of manufacturing an integrated photovoltaic device in which a plurality of photovoltaic devices each including a semiconductor layer and an upper electrode layer are arranged on the same substrate; and a step of forming an insulating film on a surface of the electrode layer or the semiconductor layer. Scribing at least the electrode layer or the semiconductor layer from the insulating film side.

In the method of manufacturing an integrated photovoltaic device according to the present invention, it is preferable that the scribing step is performed by using a laser scribe method, a sand blast scribe method, or an ultrasonic scribe method.

The insulating film is made of at least acrylic,
It is preferably formed of a polymer resin selected from polyester or polyimide.

The insulating film is made of at least SiO, S
It is preferably formed of an inorganic material selected from iO ₂ or glass.

Furthermore, it is preferable that an opening is formed in a portion of the insulating film to be scribed.

The semiconductor layer has a structure in which at least a first semiconductor layer and a second semiconductor layer are laminated in this order from the light incident side, and at least a part of the second semiconductor layer has a columnar microcrystalline structure. Is preferable.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below, but the present invention is not limited to these embodiments.

In the method of manufacturing an integrated photovoltaic device according to the present invention, by forming an insulating material on the surface of a material to be scribed, the conductive material is covered with the insulating material, and dust generated by cutting is minimized. The dust is in a state in which the insulating material is laminated on the conductive material, so the conductivity is low, and even if the dust remains in the divided groove after cutting, the short-circuit state should be minimized. Can be.

The gist of the present invention is to laminate a material having an effect of preventing the miniaturization and preventing the short circuit on the material to be cut which becomes fine conductive particles by cutting. As an insulating material, acrylic, polyester, and polyimide are preferable as long as they are organic materials, and SiO, SiO ₂ , glass and the like are suitably used as inorganic materials.

Hereinafter, the structure of the integrated photovoltaic device of the present invention and the method of manufacturing the same will be described with reference to the accompanying drawings.

FIG. 1 shows an example of the configuration of an integrated photovoltaic device according to the present invention, and (a) to (f) show the structure in each manufacturing process.

As shown in FIG. 1, the integrated type photovoltaic device of this embodiment has a metal substrate 101 made of stainless steel or the like on a silicon substrate.
An insulating layer 102 made of O ₂ , polyimide, or the like is deposited, a lower electrode 103 made of a reflective layer made of Al, Cu, Ag, or the like, and a reflection increasing layer made of zinc oxide, indium oxide, tin oxide, or the like, and a dividing groove 104. , The semiconductor layer 105,
It comprises a dividing groove 106, an upper electrode 107 made of a transparent conductive film such as ITO, and an insulating film 108.

FIG. 1A shows a state where an insulating layer 102 is deposited on the surface of a substrate 101.

FIG. 1B shows that a lower electrode 103 composed of a reflection layer and a reflection enhancement layer is further deposited,
04 separates the lower electrode 103 electrically.

FIG. 1C shows a semiconductor layer 105 deposited.
Further, a state in which a division groove 106 of the semiconductor layer 105 is formed is shown.

FIG. 1D shows a state in which a transparent conductive layer 107 serving as an upper electrode is deposited on the semiconductor layer 105 and connected in series to an adjacent semiconductor element via a division groove 106.

FIG. 1E shows a state where an insulating film 108 is deposited on the surface of the transparent conductive layer 107.

FIG. 1F shows a state in which the transparent conductive layer 107 is further electrically divided by the division grooves 109.

FIG. 2 shows another example of the structure of the integrated photovoltaic device of the present invention, and (a) to (f) show the structure in each manufacturing process.

As shown in FIG. 2, in this integrated type photovoltaic device, the substrate 101 is a glass substrate, of a type in which light is incident from the substrate side, and has no insulating layer 102 and an upper electrode layer 107. The configuration and manufacturing method are substantially the same as those in FIG. 1 except that the positional relationship between the first electrode and the lower electrode layer 103 is opposite.

FIG. 3 shows another example of the structure of the integrated photovoltaic device of the present invention, and (a) to (f) show the structure in each manufacturing process. This integrated photovoltaic element
This is an example in which only the scribe line is opened in the insulating film 108 in FIG.

In FIG. 3, a substrate 101 is a glass substrate and is of a type in which light is incident from the substrate side. There is no insulating layer 102 and the upper electrode layer 107 and the lower electrode layer 1
The configuration and manufacturing method are almost the same as those in FIG. 1 except that the positional relationship of 03 is opposite.

FIG. 4 shows still another example of the configuration of the integrated photovoltaic device of the present invention, and (a) to (f) show the structure in each manufacturing process.

As shown in FIG. 4, in this integrated type photovoltaic element, the structure and manufacturing method are the same as those in FIG. 1 except that the substrate 101 is an insulating substrate such as polyimide and the insulating layer 102 is not provided. It is.

Hereinafter, each component of the present invention will be described in more detail.

(Substrate) As the substrate 101, an insulating substrate or a conductive substrate on which an insulating layer is formed is used. Glass, polyimide, PET as insulating substrate
A resin film such as (polyethylene terephthalate) is preferably used. In particular, polyimide is preferably used because it is a film having high heat resistance.

As the conductive substrate, stainless steel, aluminum, copper, zinc steel plate or the like is preferably used. These metal plates may be cut into a certain shape and used, or may be used in the form of a long sheet. When used in the form of a long sheet, it can be wound in a coil shape, so that it is suitable for continuous production, and storage and transportation are easy. Although the surface of the substrate may be a mirror surface, appropriate irregularities may be provided for the purpose of scattering light.

(Insulating Layer 102) As the insulating layer 102 formed on the conductive substrate, at least 1 × 10 ¹⁰ Ωcm
As described above, it is necessary to have a specific resistance of preferably 1 × 10 ¹² Ωcm or more. Further, it is necessary to withstand the temperature applied during the deposition of electrodes and semiconductors (usually 200 ° C. or higher) and, in some cases, the temperature applied in laser beam processing. Materials satisfying these conditions include a diamond film, a silicon film, a silicon carbide film, a silicon nitride film, a silicon oxide film, an aluminum oxide film, a calcium fluoride film, a glass film, and a polyimide film. These films are formed on a conductive substrate by a method such as sputtering, plasma CVD, or ion plating if the film is an inorganic material, or by coating a material dissolved in a solvent with a doctor blade if the film is an organic material. A film can be formed.

(Reflection Layer) This reflection layer functions as the lower electrode 103 together with the reflection increasing layer. As the reflection layer (part of the lower electrode 103), Al, Cu, Ag, or an alloy containing these metals is preferably used, and is deposited on the substrate by a method such as sputtering, plating, plasma CVD, or ion plating. Can be done. In the case of a conductive substrate, it is formed on an insulating film formed on the conductive substrate and also functions as a lower electrode.

(Reflection increasing layer) Reflection increasing layer (lower electrode 10)
3) as zinc oxide (ZnO), tin oxide (S
nO_Two), Cadmium oxide (CdO), cadmium star
Nate (Cd_TwoSnO _Four), Indium oxide (In)
_TwoO_Three), Metal oxides such as indium tin oxide (ITO)
Preferably used, sputtering, plating, plasma C
Depositing by VD, ion plating, etc.
Can be. Even if the surface of this reflection enhancement layer has irregularities
Good.

Further, fluorine may be added to the reflection increasing layer as needed. When adjacent semiconductor elements are connected in series by adding fluorine, the specific resistance of the connection portion can be reduced, and an increase in series resistance of the semiconductor elements connected in series can be effectively prevented.

When laser light is used for dividing the lower electrode 103, that is, the reflection layer and the reflection enhancement layer, the reflection enhancement layer to which fluorine is added is a laser light in the near infrared region, for example, Y light.
Since the fundamental wave of the AG laser is effectively absorbed, division is facilitated and damage to the base or substrate is prevented. In particular, when a conductive substrate is used, it is possible to prevent the insulating layer 102 (see FIG. 1) from being broken by laser light irradiation and causing a short circuit. Also, when an insulating substrate such as a resin film is used, the resin can be prevented from being denatured by heat. Further, when the electrical connection between the upper electrode and the lower electrode is performed by laser light irradiation, the laser light irradiation may cause the reflection increasing layer of the lower electrode 103 and the semiconductor layer 105 to be separated. This phenomenon can be prevented.

Further, since the conductive layer to which fluorine is added has an n-type conductivity, when the semiconductor layer 105 in contact with the reflection increasing layer of the lower electrode 103 is an n-type semiconductor, the connection between both layers is good and the ohmic property is improved. can do. Further, in order to reduce internal stress generated at the interface between the reflection increasing layer of the lower electrode 103 and the semiconductor layer 105, light deterioration of the semiconductor element,
Vibration deterioration can be suppressed. Further, the lower electrode 10
The component of the third reflective layer can be prevented from diffusing into the semiconductor layer 105, and deterioration of the element can be suppressed. This effect is particularly remarkable when Ag, which easily causes migration, is used as the reflective layer of the lower electrode 103.

The preferred fluorine content is 0.05 to 30.
Atomic%, more preferably 0.2 to 5 atomic%.

When fluorine is contained in the reflection increasing layer, fluorine and / or a fluorine-containing gas may be used as a raw material gas and / or an atmosphere gas in the above-described method for producing a reflection layer.

(Insulating Film 108) As the insulating film 108 used in the present invention, it is necessary that the insulating film 108 fulfills the purpose of preventing a short circuit of a conductive layer for dividing a metal layer, a semiconductor layer, a transparent electrode layer, or the like. , At least 1 × 10 ¹⁰ Ωc
m, preferably 1 × 10 ¹² Ωcm or more. Further, it is necessary to withstand the temperature applied during the deposition of electrodes and semiconductors (usually 200 ° C. or higher), and if laser scribe is further performed, the temperature applied during laser processing. In addition, it is necessary to select and use a suitable material according to the scribing method, and the suitable material differs depending on whether it is used on the light incident side or on the side opposite to the light incidence. The insulating film 10
8 can be peeled off after scribing, but can also be left as a part of the constituent material of the integrated photovoltaic element.

Specific examples of such a material include a diamond film, a silicon film, a silicon carbide film, a silicon nitride film, a silicon oxide film, an aluminum oxide film, a calcium fluoride film, a glass film, and a polyimide film. . These films can be formed by a method such as sputtering, plasma CVD, or ion plating if the film is an inorganic material, or a method such as coating a material dissolved in a solvent with a doctor blade if the film is an organic material. it can.

When a laser beam is used as a scribing method, the insulating material must pass through the insulating material and reach the material to be cut. However, the insulating material is not necessarily required to be transparent. The mechanism of the present invention is a mechanism in which cutting is performed by absorbing heat to generate heat and transferring heat to a lower material.

(Scribe Method) As a method suitable for dividing the insulating film 108 in the present invention, a laser scribe method, a scribe method by sand blast, a scribe method by ultrasonic waves, or the like is used.

For the laser scribe, a YAG laser, a CO ₂ laser, an excimer laser or the like can be used, but a YAG laser is particularly preferably used. In addition to the fundamental wavelength of 1.06 μm, light of 0.53 μm of the second harmonic obtained by using a nonlinear optical element together can also be used as desired.

Although the YAG laser can perform a continuous oscillation operation, it is preferable to use it in a Q-switch pulse oscillation operation in order to obtain a high peak power and a high frequency. The frequency of Q switch pulse oscillation is about several kHz to several tens kHz, and the duration of one pulse is 100n
The time before and after sec is preferable.

FIG. 6 shows an outline of an optical system for laser processing. In FIG. 6, reference numeral 301 denotes a laser main body. A Q switch and a non-linear optical element are incorporated therein as necessary. A power source 302 turns on a laser excitation light source. A cooling device 303 circulates cooling water.
Reference numeral 304 denotes an output laser beam, which is bent by 90 degrees by the dichroic mirror 305, condensed by the lens 306, and irradiated on the sample 307. Sample 30
7 is mounted on the stage 308,
Moves in the horizontal direction at a speed determined by the controller 309, and the beam scans the sample surface. In the case of a large sample, the beam may be moved using a polygon mirror.

The light from the illumination light source 310 is collimated by the lens 311, bent by 90 degrees by the dichroic mirror 312, and irradiates the sample 307. The processing status is photographed by the ITV camera 314 via the reflection mirror 313 and can be observed on the monitor 315.

Next, a scribing method by sandblasting is shown in FIG. 7, reference numeral 401 denotes a conveyor, 4
02 denotes a substrate on which a film is deposited, 403 denotes a polishing agent for ejected fine particles, and 404 denotes a nozzle.

The scribe method by sandblasting is roughly as follows. That is, portions other than the portion where the dividing groove is formed in the substrate 402 are masked with an insulating film. Thereafter, the substrate 402 is placed on the conveyor 401 with the direction opposite to the substrate facing upward, and is conveyed at a constant speed (a speed of about 500 mm / min). Particles of SiC or the like having a particle diameter of about 10 μm are sent to the nozzle 404 and sprayed on the substrate 402 at high speed. A part of the insulating film is not scribed, and the other part is scribed to form a division groove. The depth of the groove can be controlled by the time during which the abrasive grains are sprayed on the substrate, and only the desired metal film or conductive film can be scribed.

FIG. 8 shows a scribing method using ultrasonic waves. In FIG. 8, reference numeral 501 denotes an XY stage,
02 denotes a substrate to be scribed, 503 denotes a chip, 504 denotes a horn, and 505 denotes an oscillator. The outline of the scribing method using ultrasonic waves is as follows. That is, the substrate 50
The chip 503 is pressed against the substrate 2, and the substrate 502 is linearly moved by the XY stage 501 to form a division groove. At this time, the insulating film is scribed simultaneously with the metal or semiconductor film.

Hereinafter, the semiconductor layer of the photovoltaic element in which the manufacturing method of the present invention is preferably used will be described in more detail by dividing the semiconductor layer into a p (n) layer and an i layer.

(P (n) Layer) When the p (n) layer is crystallized by post-processing, it may be amorphous or crystallized. In the case where recrystallization is not performed in the post-treatment, those that are crystallized are preferable. The p-type layer or the n-type layer is an important layer that affects the characteristics of the photovoltaic device.

An amorphous material of a p-type layer or an n-type layer,
Examples of the microcrystalline or polycrystalline material include a-Si: H, a
-Si: HX, a-SiC: H, a-SiC: HX, a
-SiGe: H, a-SiGeC: H, a-SiO:
H, a-SiN: H, a-SiON: HX, a-SiO
CN: HX, μc-Si: H, μc-SiC: H, μc
-Si: HX, μc-SiC: HX, μc-SiGe:
H, μc-SiO: H, μc-SiGeC: H, μc −
SiN: H, μc-SiON: HX, μc-SiOC
N: HX, poly-Si: H, poly-Si: H
X, poly-SiC: H, poly-SiC: HX,
poly-SiGe: H, poly-Si, poly-
A p-type valence electron controlling agent (Group III atom B, Al, Ga, In, T) in SiC, poly-SiGe, etc.
l) or n-type valence electron controlling agent (Group V atom P in the periodic table)
Materials to which As, Sb, and Bi) are added at a high concentration can be given.

In particular, the p-type layer or the n-type layer on the light incident side includes:
A crystalline semiconductor layer with little light absorption or an amorphous semiconductor layer with a wide band gap is suitable.

The amount of Group III atom added to the p-type layer and the amount of Group V atom added to the n-type layer are 0.
The optimal amount is 1 to 50 at%.

Further, hydrogen atoms (H, D) or halogen atoms contained in the p-type layer or the n-type layer work to compensate for dangling bonds of the p-type layer or the n-type layer, and n
This improves the doping efficiency of the mold layer. The optimum amount of the hydrogen atom or the halogen atom added to the p-type layer or the n-type layer is 0.1 to 40 at%. In particular, when the p-type layer or the n-type layer is crystalline, the optimum amount of hydrogen atoms or halogen atoms is 0.1 to 8 at%. Further, a preferred distribution form is one in which a large content of hydrogen atoms and / or halogen atoms is distributed on each interface side of the p-type layer / i-type layer and the n-type layer / i-type layer. The content of the hydrogen atom and / or the halogen atom is preferably in a range of 1.1 to 2 times the content in the bulk. Thus, the p-type layer / i-type layer, n
By increasing the content of hydrogen atoms or halogen atoms in the vicinity of each interface between the mold layer and the i-type layer, the defect level and mechanical strain in the vicinity of the interface can be reduced. Can increase the photovoltaic power and the photocurrent.

The p-type layer and the n-type layer of the photovoltaic element preferably have an activation energy of 0.2 eV or less, and most preferably have an activation energy of 0.1 eV or less. The specific resistance is preferably 100 Ωcm or less, and 1 Ωcm
The following are optimal. Further, the thickness of the p-type layer and the n-type layer is preferably 1 to 50 nm, and most preferably 3 to 10 nm.

As a source gas suitable for depositing the p-type layer or the n-type layer of the photovoltaic element, a gasizable compound containing a silicon atom, a gasizable compound containing a germanium atom, and a carbon atom were used. Examples thereof include a compound that can be gasified, and a mixed gas of the compound.

Specific examples of the gasizable compounds containing silicon atoms include SiH ₄ , Si ₂ H ₆ , SiF ₄ and S
iFH ₃ , SiF ₂ H ₂ , SiF ₃ H, Si ₃ H ₈ , Si
D ₄ , SiHD ₃ , SiH ₂ D ₂ , SiH ₃ D, SiFD ₃ ,
SiF ₂ D ₂ , SiD ₃ H, Si ₂ D ₃ H _{3 and the} like can be mentioned.

Specifically, a gas containing a germanium atom
The compound which can be converted to is GeH_Four, GeD_Four, GeF_Four,
GeFH_Three, GeF_TwoH_Two, GeF_ThreeH, GeHD_Three, Ge
H_TwoD _Two, GeH_ThreeD, Ge_TwoH₆, Ge_TwoD₆Etc.
You.

Specifically, it can be gasified containing carbon atoms.
As the compound, CH_Four, CD_Four, C _nH_{2n + 2}(N is integer
Number), C_nH_Two(N is an integer), C₆H₆, CO_Two, CO, etc.
No.

As the nitrogen-containing gas, N ₂ , NH ₃ , N
D ₃ , NO, NO ₂ and N ₂ O are mentioned.

As the oxygen-containing gas, O ₂ , CO, CO ₂ ,
NO, NO ₂ , N ₂ O, CH ₃ CH ₂ OH, CH ₃ OH and the like.

Examples of the substance introduced into the p-type layer or the n-type layer for controlling valence electrons include Group III and V atoms in the periodic table.

As a starting material for introducing a group III atom, specifically, for introducing a boron atom, there are B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H ₉ , B ₅ H ₁₁ , B
_{6 H 1 0, B 6 H} 12, B 6 H 14 , etc. borohydride, BF _3, B
Examples thereof include boron halide such as Cl ₃ .
In addition, AlCl ₃ , GaCl ₃ , InCl ₃ , TIC
l _{3 and the} like can be mentioned, and B ₂ H ₆ and BF ₃ are particularly suitable.

Effectively as a starting material for introducing a group V atom
Specifically, P is used for introducing a phosphorus atom.
H_Three, P_TwoH_FourPhosphorus hydride, PH_FourI, PF_Three, PF_Five, P
Cl _Three, PCl_Five, PBr_Three, PBr_Five, PI_ThreeSuch as haloge
Phosphorus nitride. In addition, AsH_Three, AsF_Three, As
Cl_Three, AsBr_Three, AsF_Five, SbH_Three, SbF_Three, Sb
F_Five, SbCl_Three, SbCl_Five, BiH_Three, BiCl_Three, B
iBr_ThreeEtc., and particularly PH_Three, PF_ThreeSuitable
are doing.

The p-type or n-type layer suitable for the photovoltaic element is deposited by RF plasma CVD, VHF plasma CVD, or microwave plasma CVD.

In particular, when depositing by RF plasma CVD, a capacitively coupled RF plasma CVD is suitable.
When a p-type layer or an n-type layer is deposited by RF plasma CVD, the substrate temperature in the deposition chamber is 100 to 350 ° C., and the internal pressure is 13.3 Pa (0.1 Torr) to 1.33 × 10 ³ P.
a (10 Torr), RF power is 0.01 to 5.0 W
/ Cm ³ and a deposition rate of 0.1 to 30 ° / sec.

The compounds capable of being gasified are H ₂ , H
It may be appropriately diluted with a gas such as e, Ne, Ar, Xe, or Kr and introduced into the deposition chamber. In particular, microcrystalline semiconductors and a-Si
When depositing a layer having a small light absorption or a wide band gap, such as C: H, it is preferable to dilute the source gas 2 to 100 times with hydrogen gas and to introduce relatively high RF and VHF power. Things. The RF frequency is preferably in the range of 1 MHz to 300 MHz, and especially 1 MHz to 300 MHz.
A frequency near 3.56 MHz is optimal.

When a p-type layer or an n-type layer is deposited by a microwave plasma CVD method, a microwave plasma CVD apparatus introduces a microwave into a deposition chamber through a dielectric window (alumina ceramics or the like) through a waveguide. The method is suitable.

When a p-type layer or an n-type layer is deposited by microwave plasma CVD, the substrate temperature in the deposition chamber is 100
400 ° C, internal pressure 0.067 Pa (0.5 mTorr)
r) to 3.99 Pa (30 mTorr), a microwave power of 0.01 to 1 W / cm ³ , and a microwave frequency of 0.5 to 10 GHz as preferable ranges.

The compounds capable of being gasified are H ₂ , H
It may be appropriately diluted with a gas such as e, Ne, Ar, Xe, or Kr and introduced into the deposition chamber.

In particular, when depositing a layer having a small light absorption or a wide band gap, such as a microcrystalline semiconductor or a-SiC: H, dilute the source gas 2 to 100 times with hydrogen gas and compare the microwave power. It is preferable to introduce extremely high power.

(I-layer) The i-layer may be either an amorphous or crystalline semiconductor layer. As the crystalline semiconductor, a microcrystalline semiconductor is preferable.

Amorphous or microcrystalline silicon suitable for the photovoltaic device of the present invention is obtained by RF plasma CVD, V
HF plasma CVD and microwave plasma CVD are preferred methods. In particular, the deposition rate of microcrystalline silicon depends on the electromagnetic wave used, and the higher the frequency, the higher the deposition rate with the same input energy.

The source gas for supplying silicon atoms suitable for the microcrystalline silicon of the present invention includes SiH ₄ , Si ₂ H ₆ ,
SiF ₄ , SiHF ₃ , SiH ₂ F ₂ , SiH ₃ F, SiH ₃
Cl, SiH ₂ Cl ₂ , SiHCl ₃ , SiCl ₄ , SiD
_{4, SiHD 3, SiH 2 D} 2, SiH 3 D, SiFD 3, S
Preferred examples include silane-based source gases such as iF ₂ D ₂ , SiD ₃ H, and Si ₂ D ₃ H ₃ .

The source gas for supplying germanium suitable for microcrystalline silicon germanium is GeH ₄ ,
GeF ₄ , GeHF ₃ , GeH ₂ F ₂ , GeH ₃ F, GeH
Cl ₃ , GeH ₂ Cl ₂ , GeH ₃ Cl, GeHD ₃ , Ge
_{H 2 D 2, GeH 3 D} , Ge 2 H 6, GeD 6 , and the like.

The source gas needs to be diluted with hydrogen gas in order to form a good amorphous or microcrystalline semiconductor. The dilution ratio with hydrogen gas is preferably 10 times or more. A particularly preferred range of the dilution ratio is from 10 to 100 times. When the dilution ratio is small, microcrystals are not formed and amorphous is formed. on the other hand,
If the dilution ratio is too high, the deposition rate of the microcrystals becomes too low, causing a practical problem. It is also possible to dilute with helium gas in addition to diluting with hydrogen.

The substrate temperature for forming microcrystals suitable for the present invention is 100 to 500 ° C. In particular, when increasing the deposition rate, it is desirable to set the substrate temperature to a relatively high temperature.

The degree of vacuum in the chamber when depositing the microcrystal of the present invention is 0.133 Pa (1 mTorr).
r) to 133 Pa (1 Torr) is a suitable range. In particular, when a microcrystalline semiconductor is deposited by a microwave plasma CVD method, the degree of vacuum is preferably about several hundred mPa. The input power to the chamber when depositing the microcrystalline semiconductor of the present invention is 0.01 to
A preferred range is 10 W / cm ³ .
In terms of the relationship between the flow rate of the source gas and the input power, a power-limited region in which the deposition rate depends on the input power is suitable.

Further, in the deposition of the amorphous or microcrystalline semiconductor of the present invention, the distance between the substrate and the electrode for power supply is an important factor. The distance between the electrodes at which an amorphous or microcrystal suitable for the present invention is obtained is in the range of 10 mm to 50 mm.

The average crystal grain size of microcrystals suitable as the microcrystalline semiconductor of the photovoltaic device of the present invention is 100 ° to 1000 °.
Å is a suitable range. Further, as for the ratio of amorphous contained in the microcrystalline semiconductor, it is desirable that the ratio of the peak related to the crystal to the peak related to the amorphous when viewed from the Raman spectrum is 70% or less. If the average crystal grain size is smaller than 100 °, a large amount of amorphous material will be present at the crystal grain boundaries, and light degradation will be exhibited. When the crystal grain size is small, the mobility and lifetime of electrons and holes are reduced, and the characteristics as a semiconductor are reduced. On the other hand, when the average crystal grain size is larger than 1000 °, the relaxation of the crystal grain boundaries does not sufficiently proceed, and defects such as dangling bonds are generated in the crystal grain boundaries, and the defects act as recombination centers of electrons and holes. As a result, the characteristics of the microcrystalline semiconductor deteriorate.

Here, the average crystal grain size of the fine crystal grains is calculated from the half value width of the (220) peak of X-ray diffraction.
It is calculated by using the following equation. Alternatively, it can be obtained from a dark field image of a transmission electron microscope. When the average particle size of the columnar microcrystals is determined using a transmission electron microscope, it is preferable that the geometric mean of the major axis and the minor axis be the average particle size.

In the present invention, it is important that microcrystals having different crystal grain sizes coexist. One method of controlling (confirming) the above is to determine the half width of the (220) peak of the X-ray diffraction. It is preferable to control the ratio of the calculated average particle size (x) of the microcrystals to the average particle size (y) of the microcrystals determined from the dark field image of the transmission electron microscope so as to be within a specific range. Specifically, it is preferable to control x / y to be 0.1 to 0.8.

This is considered to be due to the following reasons. That is, X-ray diffraction is an average particle size over a large area,
On the other hand, a transmission electron microscope is a particle size obtained by observing a local range. Therefore, because these values are different,
It can be confirmed that microcrystals having different crystal grain sizes are mixed. According to the study by the present inventors, it has been found that when x / y satisfies the above range, workability during laser processing is improved and, at the same time, a material excellent in characteristics can be obtained.

The shape of the microcrystal is preferably elongated along the direction of charge movement, that is, a columnar structure. In addition, the proportion of hydrogen atoms or halogen atoms contained in the microcrystal of the present invention is desirably 30% or less.

In the photovoltaic element, the i-layer is an important layer for generating and transporting carriers with respect to irradiation light. As the i-layer, a slightly p-type or slightly n-type layer can also be used (whether it becomes p-type or n-type depends on the distribution of intrinsic defects such as tail state).

The i-layer of the photovoltaic device of the present invention contains a silicon atom and a germanium atom in addition to a semiconductor having a uniform band gap, so that the band gap changes smoothly in the thickness direction of the i-layer. It is suitable that the minimum value of the band gap is deviated from the center position of the i-layer toward the interface between the p-layer and the i-layer. Further, those in which the valence electron controlling agent serving as a donor and the valence electron controlling agent serving as an acceptor are simultaneously doped in the i-layer are also suitable.

In particular, those having a large content of hydrogen atoms and / or halogen atoms at each interface side of the p-type layer / i-type layer and the n-type layer / i-type layer are preferred. The preferred range of the content of hydrogen atoms and / or halogen atoms in the vicinity of the interface is 1.1 to 2 times the content in the bulk. Further, it is preferable that the content of hydrogen atoms and / or halogen atoms is changed in accordance with the content of silicon atoms. A hydrogen atom at the minimum silicon atom content or /
The content of the halogen atom is preferably in the range of 1 to 10 at%, and more preferably 0.3 to 0.8 times the maximum region of the content of the hydrogen atom and / or the halogen atom.

The content of hydrogen atoms and / or halogen atoms is changed in correspondence with silicon atoms, that is, the content of hydrogen atoms and / or halogen atoms decreases in a narrow band gap corresponding to the band gap. Is what it is. Although the details of the mechanism are unknown, according to the method for forming a deposited film of the present invention, in the deposition of an alloy semiconductor containing silicon atoms and germanium atoms, each of the atoms depends on the ionization rate of the silicon atoms and germanium atoms. It is considered that there is a difference in the obtained electromagnetic wave energies, and as a result, even if the hydrogen content or / halogen content in the alloy semiconductor is small, the relaxation is sufficiently advanced and a good alloy semiconductor can be deposited.

The thickness of the i-layer depends on the structure of the photovoltaic element (eg, single cell, tandem cell, triple cell) and i
0.7 to 3 depending on the band gap of the mold layer.
0.0 μm is mentioned as an optimum layer thickness.

The i-layer containing silicon atoms or germanium atoms to which the production method of the present invention is preferably used has a small valence band tail state even when the deposition rate is increased to 50 ° / sec or more. The tilt of the tail state is 60 meV or less, and the electron spin resonance (E
The density of the dangling bonds by SR) is 10 ¹⁷ / cm ³ or less.

The band gap of the i-layer is p-layer / i-layer,
It is preferable to design so as to be wider in each interface direction of the n-layer / i-layer. With such a design, the photovoltaic power and the photocurrent of the photovoltaic element can be increased, and furthermore, it is possible to prevent light deterioration or the like when used for a long time.

Further, since the semiconductor layer 105 contains fluorine, it contributes to a reduction in series resistance during serial connection by laser irradiation. That is, the semiconductor layer 10 and the reflection increasing layer which are a part of the lower electrode 103 by the laser beam.
5. It is easy to melt and crystallize the upper electrode 107 to reduce the resistance. Further, the reflection enhancement layer and / or the upper electrode 1 which is also a part of the lower electrode 103 containing fluorine.
07 is improved.

In the case of microcrystallization, it contributes to an increase in the crystal grain size of the microcrystal. Further, fluorine effectively works as a terminator for dangling bonds in the non-single-crystal semiconductor layer.

Further, the semiconductor device to which the present invention is preferably used has a structure in which a plurality of photoelectric conversion layers are laminated (for example,
-Pin tandem structure, pin-pin-pin triple structure, etc.).

(Upper Electrode) As the upper electrode 107 made of a transparent conductive layer, the same material as that of the reflection increasing layer of the lower electrode 103 can be used. Further, it can be deposited by the same method as the reflection enhancing layer.

The upper electrode dividing groove 109 is preferably formed by a scribe method using a laser beam (laser scribe), a scribe method using sand blast, or a scribe method using ultrasonic waves.

Next, an example of a method for forming a semiconductor layer of a photovoltaic element suitable for carrying out the present invention will be described with reference to FIG.

FIG. 5 shows an apparatus for forming a deposited film for producing the photovoltaic element of the present invention. In FIG. 5, the deposition film forming apparatus includes a load chamber 201, a microcrystalline silicon i-layer chamber 202, an amorphous silicon i-layer
It comprises an RF chamber 203 of layers and an n-layer, a microcrystalline silicon germanium i-layer chamber 204, and an unload chamber 205. In the load chamber, a heater for laser annealing (not shown) and a window 222 for irradiating a semiconductor layer with a laser from a laser (not shown) are arranged.

Each chamber has a gate valve 206, 20
7, 208 and 209 are separated so that the source gases do not mix. Microcrystalline silicon i-layer chamber 202
Comprises a substrate heating heater 211 and a plasma CVD chamber 210. The RF chamber 203
Heater 212 for n-layer deposition and deposition chamber 21 for n-layer deposition
5. i-layer deposition heater 213 and i-layer deposition chamber 2
16, a heater 214 for p-layer deposition and a deposition chamber 217 for p-layer deposition. The microcrystalline silicon germanium i-layer chamber 204 has a heater 218 and a plasma CVD chamber 219. The substrate is mounted on a substrate holder 221 and is moved on rails 220 by rollers driven from the outside. Plasma CVD chambers 210 and 219
Then, microcrystals are deposited. For the microcrystal, a microwave plasma CVD method, a VHF plasma CVD method, or an RF plasma CVD method is used.

The photovoltaic device of the present invention is formed as follows.

First, the SUS substrate is set on the substrate holder 221 and set on the rail of the load chamber 201. The load chamber 201 is evacuated to a vacuum of several hundred mPa or less. Open gate valves 206 and 207,
The substrate holder 221 is placed in the n-layer deposition chamber 2 of the chamber 203.
Move to 15. Each gate valve is closed, and an n-layer is deposited to a desired thickness with a desired source gas. After exhausting enough,
The substrate holder 221 is moved to the load chamber 201. The substrate is heated by a heater (not shown) so that the substrate temperature becomes 400 ° C., and after the substrate temperature becomes constant, X (not shown)
The n-layer is crystallized with an eCl laser. The internal pressure in the load chamber 201 during laser irradiation is 0.133 Pa
(1 mTorr) or less was maintained.

Next, the substrate holder 221 is moved to the deposition chamber 202, and the gate valve 206 is closed. The substrate is heated to a desired substrate temperature by a heater 211, a required amount of a desired source gas is introduced, a desired degree of vacuum is set, and a predetermined microwave energy or VHF energy is applied to the deposition chamber 210.
And generate plasma to deposit a microcrystalline silicon i-layer on the substrate to a desired thickness. At this time, after the n-layer is subjected to hydrogen plasma treatment so that the i-layer is epitaxially grown on the n-layer, the i-layer is continuously deposited, or the substrate temperature during the deposition of the i-layer is changed to the substrate temperature during the n-layer deposition. Depositing at a higher substrate temperature is the preferred method.

Next, the chamber 203 is sufficiently evacuated,
The gate valve 207 is opened, and the substrate holder 221 is moved from the chamber 202 to the chamber 203. The substrate holder 221 is moved to the p-layer deposition chamber 217 of the chamber 203.
Then, the substrate is heated to a desired temperature by the heater 214. A source gas for p-layer deposition is supplied to the deposition chamber at a desired flow rate, and RF energy is introduced into the deposition chamber 217 while maintaining the deposition chamber at a desired degree of vacuum. Then, a p-layer is deposited to a desired thickness. After the p-layer deposition, the deposition chamber 217 is sufficiently evacuated, and the substrate holder is moved to the n-layer deposition chamber 215 in the same chamber. An n-layer is deposited on the p-layer in the same manner as the n-layer. The deposition chamber is sufficiently evacuated, and the substrate holder 221 is moved to the i-layer deposition chamber 216. The substrate temperature is heated to a predetermined temperature by the heater 213. A desired flow rate of the source gas for i-layer deposition is supplied to the deposition chamber 216,
The pressure in the deposition chamber 216 is maintained at the desired pressure to introduce the desired RF energy. The deposition chamber 216 is sufficiently evacuated, and the substrate holder 221 is moved from the deposition chamber 216 to the deposition chamber 21.
7 and the p layer is formed on the i layer in the same manner as the p layer.
Deposit the layer. After sufficiently exhausting the deposition chamber 217 as described above, the gate valves 208 and 209 are opened, and the substrate holder on which the substrate on which the semiconductor layer is deposited is set is moved to the unload chamber 205. The gate valves are all closed, nitrogen gas is sealed in the unload chamber 205, and the substrate temperature is cooled to a desired temperature. Thereafter, the take-out valve (not shown) of the unload chamber 205 is opened to take out the substrate holder. A transparent electrode is deposited on the p-layer with a desired layer thickness by a transparent electrode deposition evaporator (not shown).

[0121]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Embodiment 1 This embodiment is an example in which an integrated photovoltaic element is formed as shown in FIG. 1, and a method for manufacturing the same will be described below.

The size is 10 × 30 cm and the thickness is 150 μm.
A paste obtained by dispersing glass powder in a binder was applied to the stainless steel substrate 101 using a coater (not shown). The substrate is fired at about 700 ° C.
Was formed on the substrate 101.

Next, the sample was set in a DC magnetron sputtering device (not shown), heated to 150 ° C., and 50 sccm of Ar was introduced using an Al target, and 400 V DC was applied.
An electric power is applied to generate an Ar plasma, and the thickness is 3000 mm.
Was deposited to form a reflective layer.

Next, the substrate on which the Al film was deposited was heated at 300 ° C.
After that, 50 sccm of N ₂ gas was introduced into an RF magnetron sputtering apparatus using a ZnO target,
A ZnO film was deposited at 6000 ° to form a reflection enhancing film.

The lower electrode 103 is constituted by the reflection layer and the reflection enhancement film.

Next, the sample on which the lower electrode 103 was deposited was set on the stage of the laser beam machine shown in FIG. The laser beam is scanned by moving the stage 308 while oscillating the YAG laser, and the lower electrode dividing groove 1 having a width of 100 μm is formed.
04, the lower electrode 103 made of ZnO and Al was divided into 20 pieces with a width of 1.5 cm. At this time, the continuous oscillation output of the laser was 8 W, the oscillation frequency was 4 kHz, and the scanning speed was 5 cm / sec.

Subsequently, using the apparatus shown in FIG. 5, a semiconductor layer 105 composed of three layers, i.e., an n-layer, an i-layer, and a p-layer, was formed by a plasma CVD method according to the above-described procedure.

After forming the semiconductor layer 105, the semiconductor layer 105 is set again on the laser beam machine shown in FIG. 6, and the laser beam is scanned by moving the stage 308 while oscillating the YAG laser, and the width 1
A semiconductor dividing groove 106 of 00 μm is formed, and a semiconductor layer 10 is formed.
5 was divided into 20 with a width of 1.5 cm. At this time, the semiconductor dividing groove 106 was formed so as to be shifted from the lower electrode dividing groove 104 by about 100 μm.

After forming the semiconductor dividing groove, ITO is deposited on the semiconductor layer 105 by sputtering using an ITO target at a thickness of 500 ° using Ar as a sputtering gas to form an upper electrode layer 107 made of a transparent conductive film. Serialization was performed via the dividing groove 106.

Next, an insulating film 108 was formed as follows. A main agent composed of an acrylic resin, a curing agent composed of an isocyanate, and a solvent were mixed, discharged from a spray nozzle (not shown), and coated on the upper electrode layer 107.
After curing in an oven, it is placed on an XY stage, set again on the laser processing machine in FIG. 6, and while oscillating the YAG laser, moves the stage 308 and scans the laser beam to form the upper electrode dividing groove 109 having a width of 200 μm. The upper electrode layer 107 was divided into 20 pieces with a width of 1.5 cm. At this time, the upper electrode dividing groove 109 was formed so as to be shifted from the semiconductor dividing groove 106 by about 100 μm.

Through the above steps, an integrated photovoltaic device connected in series in 20 stages was obtained. The same steps were repeated to produce a total of 10 integrated photovoltaic elements.

Further, the width of the upper electrode dividing groove 109 is set to 15
The thickness was reduced to 0 μm, 100 μm, and 50 μm, and ten integrated photovoltaic elements were prepared in the same manner as described above.

Next, resin sealing (encapsulation) of these samples was performed as follows. First, the substrate 10
EVA was laminated on the top and bottom of Sample No. 1. At this time, E on the light incident surface side
The thickness of VA was 250 μm. Further, a fluororesin film is laminated on the light incident side, and a metal plate is laminated on the back side.
Hold for 0 minutes and perform vacuum lamination.

Next, the initial characteristics of the obtained sample were measured according to JIS.
The output was measured as specified in the method for measuring the output of an amorphous solar cell module of C8935. First, AM
1.5 100mW / c in global solar spectrum
The solar cell characteristics were measured using a pseudo solar light source (hereinafter referred to as a simulator manufactured by SPIRE) having a light quantity of m ² , and the conversion efficiency was determined to be good.
It was as low as 5%. Further, the shunt resistance was 500 kΩ · cm ² on average irrespective of the width of the dividing groove, and was a good value. This indicates that the scribe portion is good without shunting.

The reliability tests of these samples were performed according to JIS C
The test was performed based on the high-temperature and high-humidity test specified in the environmental test method and the durability test method of the amorphous solar cell module of 8938.

After the test, the sample was measured for solar cell characteristics using a simulator in the same manner as in the initial stage. As a result, no significant deterioration in the initial conversion efficiency occurred. Also, there was no significant decrease in shunt resistance.

From the results of this example, it can be seen that the integrated photovoltaic device obtained by the manufacturing method of the present invention has good characteristics, prevents shunting, has a good yield, and has high reliability. I understand.

The same effect was obtained by replacing the insulating film 108 with polyester or polyimide.

Example 2 In this example, an integrated photovoltaic element was deposited in substantially the same manner as in Example 1 except that the substrate was a glass substrate. A method of manufacturing the integrated photovoltaic device according to the present embodiment will be described with reference to FIG.

First, the upper electrode layer 1 was formed on the glass substrate 101.
07, laser scribe is performed to form an upper electrode dividing groove 109 (FIG. 3B). After forming the semiconductor layer 105, the semiconductor layer 105 is set again in the laser processing machine of FIG. The semiconductor dividing groove 106 was formed, and the semiconductor layer 105 was divided into 20 with a width of 1.5 cm (FIG. 2C). Further, an Al film was deposited to form a lower electrode 103 (FIG. 3D).

Next, only the portion where the insulating film 108 was scribed was opened with a width of 200 μm and formed as follows. First, a paste in which a polyester resin was dissolved in a solvent was prepared, and the paste was printed by a screen printing method so as to have a negative pattern of a scribed pattern. Then, it is put into a drying furnace, and the solvent is removed to remove the insulating film 10.
8 was formed (FIG. 3E).

Next, the lower electrode 103 was set in a sand scribe processing machine shown in FIG. 7 and a lower electrode dividing groove 104 was formed by ejecting abrasive particles of SiC having a particle diameter of 20 μm from a nozzle to form a lower electrode dividing groove 104 having a width of 1.5 cm. It was divided into 20 (FIG. 3 (f)).
At this time, the insulating film 108 was not scribed, and only the lower electrode in the opening was scribed. In this case, the insulating film 108 has a function as a mask. At this time, the lower electrode dividing groove 104 was formed so as to be shifted from the semiconductor dividing groove 106 by about 100 μm.

Through the above steps, an integrated photovoltaic device connected in series in 20 stages was obtained. The same steps were repeated to produce a total of 10 integrated photovoltaic elements.

Further, the width of the lower electrode dividing groove 104 is set to 15
The thickness was reduced to 0 μm, 100 μm, and 50 μm, and ten integrated photovoltaic elements were prepared in the same manner as described above.

Next, resin sealing (encapsulation) of these samples was performed in the same manner as in Example 1.

Next, the initial characteristics of the obtained sample were measured in the same manner as in Example 1. First, solar cell characteristics were measured using a pseudo solar light source (hereinafter referred to as a simulator manufactured by SPIRE) having a light amount of 100 mW / cm ^{2 in} the AM1.5 global sunlight spectrum, and the conversion efficiency was determined. There was little variation. Also, the shunt resistance is 50 on average irrespective of the width of the lower electrode dividing groove 104.
0 kΩ · cm ² , which was a good value. This indicates that the scribe portion is good without shunting.

The reliability test of these samples was performed in the same manner as in Example 1 based on the high-temperature and high-humidity test specified in the environmental test method and the durability test method of the JIS C8938 amorphous solar cell module.

After the test, when the solar cell characteristics of the sample were measured using a simulator in the same manner as in the initial stage, no significant deterioration occurred in the initial conversion efficiency. Also, there was no significant decrease in shunt resistance.

From the results of this example, it can be seen that the integrated photovoltaic device obtained by the manufacturing method of the present invention has good characteristics, prevents shunting, has a good yield, and has high reliability. I understand.

(Comparative Example 1) This comparative example is an example in which the integrated photovoltaic device having the conventional configuration shown in FIG.

After forming up to the lower electrode 103 on the glass substrate 101 in the same manner as in Example 2, the insulating film 108 (FIG.
Ref.), The lower electrode 103 was divided by a laser scribe method to produce an integrated photovoltaic element.

The width of the dividing groove 104 of the lower electrode is 2
Samples having the sizes of 00, 150, 100, and 50 μm were prepared.

Next, lamination of this sample was performed in the same manner as in Example 1.

When the characteristics of the solar cell and the shunt resistance were measured in the same manner as in Example 1, the conversion efficiency was 5% lower than that of Example 2 as a relative value, and as shown in FIG. Becomes narrower as
In the μm width, it was about 30% of Example 2.

When a reliability test was performed, FIG.
As shown in FIG.
In the case of a narrower m, the shunt resistance was reduced by about 40% compared to the initial stage. When a reverse bias was applied to the sample of Comparative Example 1 and observed with an infrared camera (not shown), it was found that the scribe portion was short-circuited.

From Example 2 and this comparative example, it can be seen that the integrated photovoltaic device obtained by the manufacturing method of the present invention has a higher yield and higher reliability than the conventional device.

Example 3 An integrated photovoltaic element shown in FIG. 3 was produced in the same manner as in Example 1 except that the substrate was a polyimide film.

First, an Al film was deposited on the substrate 101, a ZnO film was deposited as a reflection layer at 6000 °, and a reflection enhancement film was formed to form the lower electrode 103.

Next, the sample on which the lower electrode 103 was deposited was placed on the lower electrode dividing groove 1 having a width of 100 μm using the laser beam machine shown in FIG.
No. 04, and a lower electrode made of ZnO and Al having a width of 1.
It was divided into 20 at 5 cm.

Subsequently, after forming the semiconductor layer 105, FIG.
And a semiconductor dividing groove 106 having a width of 100 μm was formed, and the semiconductor layer 105 was divided into 20 with a width of 1.5 cm. At this time, the semiconductor dividing groove 106 was formed so as to be shifted from the lower electrode dividing groove 104 by about 100 μm.

After the formation of the semiconductor dividing groove, a transparent conductive layer (upper electrode) 107 was formed, and serialization was performed via the semiconductor dividing groove 106.

Next, as the insulating film 108, SiO ₂ was formed using a sputtering device (not shown). Thereafter, the upper electrode division groove 109 having a width of 200 μm is formed again on the laser processing machine shown in FIG.
It was divided into 0. At this time, the upper electrode dividing groove 109 was formed so as to be shifted from the semiconductor dividing groove 106 by about 300 μm.

Through the above steps, an integrated photovoltaic device connected in series in 20 stages was obtained. Repeat the same process,
A total of ten integrated photovoltaic elements were produced.

Next, resin sealing (encapsulation) of these samples was performed in the same manner as in Example 1.

Next, the initial characteristics of the obtained sample are shown in Example 1.
The measurement was performed in the same manner as described above. First, solar cell characteristics were measured using a simulated solar light source (hereinafter referred to as a simulator manufactured by SPIRE) having a light intensity of 100 mW / cm ^{2 in} the AM1.5 global sunlight spectrum, and the conversion efficiency was determined. There was little variation. Also, the shunt resistance was 500 kΩ · cm ^{2 on} average, which was a good value. This indicates that the scribe portion is good without shunting.

The reliability test of these samples was performed in the same manner as in Example 1 based on the high-temperature and high-humidity test specified in the environmental test method and the durability test method of the amorphous solar cell module according to JIS C8938.

After the test, when the solar cell characteristics of the sample were measured using a simulator in the same manner as in the initial stage, no significant deterioration in the initial conversion efficiency occurred. Also, there was no significant decrease in shunt resistance.

From the results of this example, it can be seen that the integrated photovoltaic device obtained by the manufacturing method of the present invention has good characteristics, prevents shunts, has a good yield, and has high reliability. I understand.

The insulating film 108 is made of Si instead of SiO _2.
Similar effects were obtained with O and glass films.

[0171]

As described above, according to the present invention,
Since the manufacturing method of the integrated photovoltaic element has a step of forming an insulating film on the surface of the electrode layer or the semiconductor layer, and a step of scribing at least the electrode layer or the semiconductor layer from the insulating film side, The dust generated by the scribing is in a state where the insulating film is laminated on the conductive material, so that the conductivity becomes low, and even if the dust remains in the divided groove after cutting, the short-circuit state is minimized. be able to. Therefore, it is possible to obtain an integrated photovoltaic element having good yield and high reliability in long-term use.

Further, since the scribe step is performed by using a laser scribe method, a sand blast scribe method, or an ultrasonic scribe method, a scribe groove can be formed narrow, and an integrated photovoltaic device having good characteristics can be obtained. can get.

Further, an insulating film is formed of at least a polymer resin selected from acryl, polyester, or polyimide, or at least SiO, Si
By forming the insulating film using an inorganic material selected from O ₂ or glass, the yield can be further improved and a more reliable integrated photovoltaic device can be obtained.

By forming an opening in a portion of the insulating film to be scribed, productivity can be improved.

Further, the semiconductor layer has a structure in which at least a first semiconductor layer and a second semiconductor layer are laminated in order from the light incident side, and at least a part of the second semiconductor layer is formed of a silicon layer having a columnar microcrystalline structure. With this configuration, the yield can be further improved, and a more reliable integrated photovoltaic device can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a method for manufacturing an integrated photovoltaic device according to the present invention, wherein (a) to (f) show structures in respective manufacturing steps.

FIGS. 2A to 2F are schematic diagrams showing another example of a method for manufacturing an integrated photovoltaic device according to the present invention, wherein FIGS.

FIGS. 3A to 3F are schematic views showing another example of a method for manufacturing an integrated photovoltaic device according to the present invention, wherein FIGS.

FIG. 4 is a schematic view showing another example of the method for manufacturing an integrated photovoltaic element according to the present invention, wherein (a) to (f) show structures in respective manufacturing steps.

FIG. 5 is a schematic view showing an apparatus for depositing a semiconductor film of an integrated photovoltaic device according to the present invention.

FIG. 6 is a schematic view showing a laser scribe method in the present invention.

FIG. 7 is a schematic view showing a sandblast scribe method in the present invention.

FIG. 8 is a schematic view showing an ultrasonic scribe method according to the present invention.

FIG. 9 is a diagram showing excellent characteristics of the integrated photovoltaic device according to the present invention.

FIG. 10 is a diagram showing the reliability of an integrated photovoltaic device according to the present invention.

FIG. 11 is a schematic diagram showing a configuration example of a conventional integrated photovoltaic element.

[Explanation of symbols]

 Reference Signs List 101 substrate 102 insulating layer 103 lower electrode 104 lower electrode dividing groove 105 semiconductor layer 106 semiconductor dividing groove 107 upper electrode 108 insulating film 109 upper electrode dividing groove 201 load chamber 202 i-layer chamber 203 p, n-layer RF chamber 204 silicon germanium i-layer Chamber 205 Unload chamber 206, 207, 208, 209 Gate valve 210 Plasma CVD chamber 211 Heater for substrate heating 212 Heater for n-layer deposition 213 Heater for i-layer deposition 214 Heater for p-layer deposition 215 n-layer deposition chamber 216 i-layer Deposition chamber for deposition 217 Deposition chamber for p-layer deposition 218 Heater 219 Plasma CVD chamber 220 Rail 221 Substrate holder 222 Window 301 Laser body 302 Power supply 303 Cooling device 304 Laser Beam 305 Dichroic mirror 306 Lens 307 Sample 308 Stage 309 Controller 310 Irradiation light source 311 Lens 312 Dichroic mirror 313 Reflection mirror 314 ITV camera 315 Monitor 401 Conveyor 402 Film-formed substrate 403 Abrasive grains 404 Nozzle 501 Conveyor 502 Film-formed substrate 50 Horn 505 ultrasonic transducer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Taketo Yoshino 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yoshifumi Takeyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Within non-corporation (72) Inventor Koji Tsuzuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. F-term (reference) 5F051 AA04 AA05 BA17 EA09 EA10 EA16 EA18

Claims (6)

[Claims] At least a lower electrode layer, a semiconductor layer,
In a method for manufacturing an integrated photovoltaic element in which a plurality of photovoltaic elements each including an upper electrode layer are arranged on the same substrate, a step of forming an insulating film on a surface of an electrode layer or a semiconductor layer; Scribing at least the electrode layer or the semiconductor layer from the side. 2. The method according to claim 1, wherein the scribing step is performed using a laser scribe method, a sand blast scribe method, or an ultrasonic scribe method.
3. The method for manufacturing an integrated photovoltaic device according to 1. 3. The insulating film according to claim 1, wherein the insulating film is formed of at least a polymer resin selected from acryl, polyester, and polyimide.
3. The method for manufacturing an integrated photovoltaic device according to 1. 4. The insulating film is made of at least SiO, Si
_{3. The} method of manufacturing an integrated photovoltaic device according to claim 1, wherein the method is formed of an inorganic material selected from O ₂ and glass. 5. The method for manufacturing an integrated photovoltaic device according to claim 1, wherein an opening is formed in a portion of the insulating film to be scribed. 6. A silicon layer in which the semiconductor layer has a structure in which at least a first semiconductor layer and a second semiconductor layer are laminated in order from a light incident side, and at least a part of the second semiconductor layer has a columnar microcrystalline structure. The method for manufacturing an integrated photovoltaic device according to claim 1, wherein: