JPH06140648A - Solar cell and manufacture thereof - Google Patents

Abstract

PURPOSE:To prevent charge produced in a semiconductor layer from leaking through a low resistance defective part by a method wherein the low resistance defective part is selectively insulated with electro-deposited resin and a shunt resistance is increased to exceed a specific value to increase the electrical resistance of the low resistance defective part. CONSTITUTION:Semiconductor layers 103, 104 and 105 which have at least one junction and electrodes 102 and 106 are built up on a conductive substrate 101 to compose a solar cell. The low resistance defective part 109 of the solar cell is selectively insulated with electro-deposited resin 110. With the constitution, a shunt resistance which is the electrical resistance of the low resistance part is increased to exceed 1X10<3>cm<2> and charge produced in the semiconductor layer can be prevented from leaking through the defective part 109, so that the characteristics of the solar cell such as the conversion efficiency of an optoelectric transducer can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a highly reliable solar cell and its manufacturing method. More specifically, the shorts and shunts that occur in the solar cell manufacturing process are repaired,
The present invention relates to a solar cell having high initial characteristics and high reliability, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Solar cells, which are photoelectric conversion elements that convert sunlight into electric energy, are widely applied as a power source for consumer appliances such as calculators and wristwatches, and also substitute fossil fuels such as petroleum and coal. It is drawing attention as a technology that can be put to practical use as power for use.

A solar cell is a technique utilizing the diffusion potential generated at a pn junction of a semiconductor. A semiconductor such as silicon absorbs sunlight to generate photo carriers of electrons and holes, and the photo carriers are pn. It is taken out to the outside by drifting by the internal electric field generated by the diffusion potential of the junction.

The method for manufacturing a solar cell is almost performed by a vacuum process used for manufacturing a semiconductor element. Specifically, a p-type or n-type crystal growth method such as the CZ method is used.
A single crystal of silicon whose valence electrons are controlled is prepared in a mold, and the single crystal is sliced to prepare a silicon wafer having a thickness of about 300 μm. Further, a pn junction is formed by forming layers of different conductivity types by an appropriate means such as diffusing a valence electron control agent so as to have a conductivity type opposite to that of the wafer.

By the way, since such a solar cell manufacturing method uses a vacuum process for manufacturing a semiconductor, there is a problem that the production cost is high and the cost is higher than that of the existing power generation method.

Under these circumstances, cost reduction is an important technical issue in the practical application of solar cells for electric power use, and various studies have been made. Materials with low cost and high conversion efficiency are being studied. Materials and other materials are being sought. Materials for such solar cells include tetrahedral amorphous semiconductors such as amorphous silicon, amorphous silicon germanium, and amorphous silicon carbide, group II-IV such as CdS and Cu ₂ S, and III such as GaAs and GaAlAs.
Examples thereof include group V compound semiconductors. In particular, thin-film solar cells using amorphous semiconductors have advantages such as the ability to form a large-area film, the thin film thickness, and the ability to deposit on any substrate material, compared to single-crystal solar cells. Promising.

The structure of an amorphous silicon solar cell is
For example, when light is incident from the side opposite to the substrate, a lower electrode is provided on the substrate, a semiconductor junction composed of a thin p-layer, an i-layer, and an n-layer is stacked on the lower electrode, and an upper electrode is further provided. Has become. Further, a grid electrode and a bus bar are provided for collecting electricity.

Amorphous silicon has a disadvantage that conversion efficiency is low because the film quality is inferior to that of crystalline silicon or polycrystalline silicon, but in order to solve this problem, two or more semiconductor junctions are stacked in series. Tandem cells are also being considered.

By the way, when the above-mentioned solar cell is used for supplying electric power to a general household, for example, an output of about 3 KW is required. If a solar cell with a conversion efficiency of 10% is used, a solar cell with a large area of 30 m ² is required. However, it is difficult to make a defect-free solar cell over a large area due to the manufacturing process of a solar cell. For example, in a polycrystal, a low resistance part occurs at the grain boundary part, or a thin film such as amorphous silicon. In a solar cell, pin holes and defects are generated due to the influence of dust during the formation of a semiconductor layer, which causes shunts and shorts. It is known that these shunts and shorts significantly reduce the conversion efficiency.

The cause of pinholes and defects and their effects will be described in more detail. For example, in the case of an amorphous silicon solar cell deposited on a stainless steel substrate, the substrate surface is not a completely smooth surface and scratches or dents,
Alternatively, because of the presence of spike-shaped protrusions and the provision of a back reflector with unevenness for the purpose of irregularly reflecting light on the substrate, a thin semiconductor layer with a thickness of several hundred Å such as p and n layers is It is not possible to completely cover such a surface, or another cause is that pinholes are generated due to dust during film formation. The semiconductor between the lower electrode and the upper electrode of the solar cell is lost due to the pinhole, and the lower electrode and the upper electrode are in direct contact with each other. If the shunt or short circuit has low resistance, if not completely lost, the current generated by light will flow in parallel to the upper electrode and flow into the low resistance part of the shunt or short circuit. Can happen to be lost. If there is such a current loss, the open circuit voltage of the solar cell will drop. In particular, when a solar cell is used when the light intensity is low, the magnitude of the current generated by the light and the leak current due to the shunt do not change so much, so that the open-circuit voltage drops significantly.

In an amorphous silicon solar cell, the sheet resistance of the semiconductor itself is generally high, so a transparent upper electrode over the entire surface of the semiconductor is required.
A conductive antireflection film such as O ₂ or ITO (In ₂ O ₃ + SnO ₂ ) is provided. For this reason, even in the case of a minute defect, the current flowing into the defect becomes considerably large. Furthermore, when the defect is located away from the grid electrode or bus bar, the resistance when flowing into the defect is large, so the current loss is relatively small, but conversely, when the defect is under the grid electrode or bus bar. The defect causes a larger current loss. On the other hand, in the defective portion due to the pinhole-like defect, not only the charge generated in the semiconductor layer leaks to the defective portion, but also an ionic substance is generated due to the interaction with moisture, so that when the solar cell is used, There is a phenomenon in which the electric resistance of the defective portion gradually decreases with the lapse of use time, and characteristics such as conversion efficiency deteriorate.

When the short circuit or the shunt is generated as described above, the current loss is reduced by removing or insulating the upper electrode at that location. As a method of selectively removing the upper electrode of the shunt or the short portion, for example, a so-called passivation method disclosed in US Pat. No. 4,729,970 is used. The method includes AlCl ₃ , ZnCl ₂ , SnCl ₄ , and SnC.
by immersing the solar cell and the counter electrode in a solution of a Lewis acid such as l ₂ or TiCl ₄ and applying a voltage to change the stoichiometric ratio of the transparent conductive oxide electrode to obtain high resistance. is there. However, even if the upper electrode has a high resistance as described above, there is a problem that a short circuit occurs again when the grid electrode is formed in the shunt portion when the grid is provided. As a measure against such a problem, only the defective portion is selectively covered with an insulating material or a material having a sufficiently high resistance to prevent a shunt or a short circuit, so that a transparent electrode, a grid electrode, or a bus bar is formed. Increasing the contact resistance of is an effective means to prevent the reduction of conversion efficiency.

As a method of selectively insulating only the defective portion of the solar cell, as disclosed in US Pat. No. 4,197,141, a polycrystalline solar cell is immersed in an electrolyte solution and an electric field is applied. There is a method of applying and oxidizing a polycrystalline grain boundary or a defective portion due to lattice mismatch, or depositing an insulator on the defective portion, or etching the defective portion. According to the invention, there is a concept of selectively depositing an insulator, but it is the content of depositing an oxide of a metal such as aluminum, chromium, or copper, and the deposition of an organic polymer material is not mentioned. . Further, the disclosed embodiment is an example of anodizing a defective portion of a gallium arsenide solar cell, and it is not disclosed whether a similar technique can be used for a silicon solar cell or the like. On the other hand, as disclosed in US Pat. No. 4,451,970, a defective portion of a solar cell is detected by a detector,
Then, there is a method of applying an insulating material to the detected defective portion with an applicator.

However, in the above-mentioned method, both the detector of the defective portion and the applicator are considerably large devices, and they can be detected only in a range larger than the actual size of the defect, and insulation is not necessary. There is a problem that the grid electrode cannot be printed because it is performed up to a portion and the height is raised. Further, there is a problem that the substrate or the applicator needs to be swept, and the processing speed is slow.

[0015]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems in solar cells and to provide a solar cell structure having good characteristics.

Another object of the present invention is to provide a method of manufacturing a solar cell which has good mass productivity and high reliability.

[0017]

In order to achieve the above-mentioned object, the solar cell of the present invention is a solar cell in which a semiconductor layer having at least one junction and an electrode are laminated on a conductive substrate. Defects with low resistance are selectively insulation-coated with electrodeposition resin, and the shunt resistance is 1 × 10 ³ Ωc
It is characterized in that it is m ² or more.

The electrodeposition resin is provided on the electrode or between the electrode and the semiconductor layer, or the electrode of the defective portion is selectively removed, and the removed portion is a system. It is characterized by being coated with an electrodeposition resin.

The size of the electrodeposition resin is preferably 10 times or less the size of the defective portion.

The method for producing a solar cell according to the present invention is the method for producing a solar cell in which a semiconductor layer having at least one junction and an electrode are laminated on a conductive substrate, and after forming the semiconductor layer, a defective portion is formed. An electrodeposition resin film is selectively formed on the electrode, and then the electrode is formed.

Another embodiment of the method for producing a solar cell according to the present invention is the method for producing a solar cell in which a semiconductor layer having at least one junction and an electrode are laminated on a conductive substrate. After the electrodes are sequentially formed, an electrodeposition resin film is selectively formed on the defective portion. After forming the electrode, it is preferable to remove the electrode in the defective portion before forming the electrodeposition resin film, and it is preferable to apply an electric field and perform forming before removing the electrode in the defective portion.

Further, a desirable mode of the method for manufacturing a solar cell of the present invention is to perform electrodeposition by applying a reverse bias equal to or lower than the breakdown voltage of the solar cell. In addition, the forward bias is applied so that the forward current of the solar cell becomes equal to or less than twice the shunt current to perform electrodeposition.

[0023]

The present invention is based on the findings of the experiments conducted by the inventors of the present invention regarding the method of manufacturing a solar cell for selectively insulating a low resistance portion caused by a defect existing in the solar cell, and further studying the findings. It has been completed. The essence is that the solar cell is dipped in the electrodeposition paint, and by applying an appropriate voltage to the solar cell, the electrodeposition paint is deposited only on the low resistance part of the solar cell, and The resistance becomes sufficiently high to prevent the charge generated in the semiconductor layer from leaking to the defective portion. As a result, the solar cell characteristics such as the conversion efficiency of the photoelectric conversion element can be improved.

Since the defective portion is insulated with the electrodeposition coating, the penetration and adsorption of water to the defective portion is strongly suppressed, so that the phenomenon of deterioration of the solar cell characteristics with the passage of use time that occurs during actual use is also significantly reduced. Be improved.

Further, in the case of a solar cell having a structure in which a grid electrode is provided on the upper electrode, since the defective portion is covered with an electrically insulating resin, the defective portion and the grid electrode are directly electrically connected. It is possible to prevent shunts caused by being performed.

An example of the structure of the solar cell of the present invention will be described below with reference to the drawings.

An example of the solar cell of the present invention is shown in FIGS.
3 to 8 schematically show structural examples of a basic solar cell.

1 and 2 show an example of the solar cell of the present invention in which the defective portion is insulation-coated with an electrodeposition resin. 3 is an amorphous silicon solar cell in which light is incident from the side opposite to the substrate, FIG. 4 is a solar cell having a triple structure of the solar cell of FIG. 3, and FIG. 5 is a thin film solar cell such as amorphous silicon deposited on a glass substrate. Light is incident from the glass substrate side. Figure 6
Is a crystalline solar cell, FIG. 7 is a thin-film polycrystalline solar cell, and FIG.
FIG. 8 is a view of the solar cell having the configuration of FIGS. 3, 4 and 7 as viewed from the light incident side. In the figure, 100 is a solar cell main body, 10
1 is a substrate, 102 is a lower electrode, 103 is an n layer, 104 is an i layer, 105 is a p layer, 106 is an upper electrode, 107 is a grid electrode, 108 is a bus bar, l09 is an electrodeposition resin, 11
0 represents a defective portion. In the figure, of the pair of electrodes that make up the solar cell, the electrode on the light incident side is called the upper electrode. Further, the conductive substrate of the present invention means a substrate and a lower electrode (when the substrate is transparent and light is incident from the substrate side, that is, in the case of FIG. 5,
However, when the substrate has conductivity, the lower electrode (or upper electrode) is not particularly required.

The substrate 101 is a semiconductor layer 103, 104, 1 in the case of a thin film solar cell such as amorphous silicon.
05 is a member that mechanically supports 05, and may also serve as one of the electrodes, as described above. The substrate 101 is required to have heat resistance to withstand the heating temperature for forming the semiconductor layers 103, 104, and 105, but it may be a conductive material or an electrically insulating material. Fe, Ni, Cr, Al, M
Metals such as o, Au, Nb, Ta, V, Ti, Pt, Pb, and Ti, or alloys thereof, such as brass, thin plates of stainless steel and their composites, carbon sheets, galvanized steel plates, etc. As the insulating material, polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polyimide, a film or sheet of heat-resistant synthetic resin such as epoxy, or these and glass fiber, carbon fiber , Composites with boron fibers, metal fibers, etc., and metal thin films of different materials and / or SiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , A on the surface of thin plates of these metals, resin sheets, etc.
Examples thereof include those obtained by subjecting an insulating thin film such as 1N or the like to a surface coating treatment by a sputtering method, a vapor deposition method, a plating method, etc., and glass, ceramics and the like.

The lower electrode 102 is composed of the semiconductor layers 103 and 10
It is one electrode for taking out the electric power generated at 4, 105, and is required to have a work function that makes an ohmic contact with the semiconductor layer 103. As the material, Al, Ag, Pt, Au, Ni, Ti, M
o, W, Fe, V, Cr, Cu, stainless steel, brass, nichrome, SnO ₂ , In ₂ O ₃ , ZnO, ITO
So-called simple metal or alloy such as (In ₂ O ₃ + SiO ₂ ) or transparent conductive oxide (TCO) is used. The surface of the lower electrode 102 is preferably smooth, but may be textured in the case of causing diffuse reflection of light.

As the semiconductor layer of the solar cell used in the present invention, pin-junction amorphous silicon, pn-junction polycrystalline silicon, pn-junction crystalline silicon, CuInSe ₂ / Cd
Compound semiconductors such as S may be mentioned. In the amorphous silicon solar cell, as a semiconductor material forming the i layer 104, a-Si: H, a-Si: F, a-Si:
H: F, a-SiGe: H, a-SiGe: F, a-S
iGe: H: F, a-SiC: H, a-SiC: F, a
Examples include so-called group IV and group IV alloy-based amorphous semiconductors such as —SiC: H: F. p layer 105 or n
The semiconductor material forming the layer 103 is obtained by doping the above-described semiconductor material forming the i-layer 104 with a valence electron control agent. Further, as a raw material, as a valence electron control agent for obtaining a p-type semiconductor,
A compound containing a Group II element is used. Examples of Group III elements include B, Al, Ga, and In. n
As a valence electron control agent for obtaining a type semiconductor, a compound containing an element of the periodic table V is used. Examples of the Group V element include P, N, As, and Sb.

The solar cell of the present invention can be used in a so-called tandem cell in which two or more semiconductor junctions are laminated for the purpose of improving spectral sensitivity and voltage.

The upper electrode 106 is composed of the semiconductor layers 103 and 10
Electrodes for extracting the electromotive force generated at 4, 105, which form a pair with the lower electrode 102. The upper electrode 106 is necessary in the case of a semiconductor having a high sheet resistance such as amorphous silicon, and is not particularly necessary in a crystalline solar cell since the sheet resistance is low. Further, since the upper electrode 106 is located on the light incident side, it needs to be transparent and is also called a transparent electrode. The upper electrode 1
06 has a light transmittance of 85% or more in order to efficiently absorb light from the sun or a white fluorescent lamp in the semiconductor layer. Further, electrically, a semiconductor generates a current generated by light. It is desirable that the sheet resistance value is 100 Ω / □ or less so that the sheet flows laterally with respect to the layer. As materials having such characteristics, SnO ₂ , In ₂ O ₃ , Z
nO, CdO, CdSnO ₄ , ITO (In ₂ O ₃ + Sn
Metal oxides such as O ₂ ) may be mentioned.

The electrodeposition resin 109 is used to insulate a defective portion 110 due to a short circuit or a shunt caused by a pinhole, a grain boundary, a spike-shaped defect of the substrate 101 and the lower electrode 102, or other causes.
It also has the function of improving moisture resistance. Although the shunt resistance of the solar cell is ideally infinite, it is generally about 1 KΩcm ² , and the shunt resistance of this level does not affect the conversion efficiency of the solar cell. However, there are shunts and shorts due to defects and 1KΩcm.
^{When it is 2} or less, the conversion efficiency is significantly reduced.

It is necessary that the electrodeposition resin is directly deposited on the defective portion, and the area of the deposited electrodeposition resin may be at least the defective portion, and is preferably 10 times or less. When the area of the deposited electrodeposition resin is larger than 10 times that of the defective portion, the number of contacts between the upper electrode and the grid electrode is reduced, the series resistance is increased, and the collection efficiency of the grid electrode is reduced.

Since the electrodeposition resin is required to have a coverage of 1 to 10 times the area of the defective portion of the solar cell, it is preferable that the electrodeposition resin deposited near the defective portion transmits sunlight.
That is, it is preferable that the electrodeposition resin is transparent.

It is necessary that the electrodeposition resin is not formed on a portion other than the defective portion of the solar cell. For this purpose, it is required that unnecessary paint can be easily washed off after electrodeposition. It is necessary that the film temperature (MFT) is preferably 50 ° C. or higher.

In order to form a uniform film, it is important for these electrodeposition resins to be stably suspended without precipitation in the solution. For this purpose, the resin should be colloidal particles of appropriate size. It is desirable that The particle size of the colloidal particles is preferably in the range of 10 nm to 100 nm, and the particle size is preferably monodisperse.
The weight average molecular weight of the skeleton resin constituting the colloidal particles is preferably about 1,000 to 20,000. It is also possible to disperse a filler such as an inorganic pigment, a ceramics, a glass frit, or a fine particle polymer in the electrodeposition resin in order to improve light resistance, heat resistance, moisture resistance, selectivity of defective portions, etc. To use.

In order to selectively and effectively insulate the defective portion of the solar cell, it is preferable that the weight of the electrodeposition film per unit amount of electricity is large. For this purpose, the Coulomb efficiency of the electrodeposition coating is 10 mg / It is preferably C or more.

As a solvent for the electrodeposition paint, a solution containing a concentration of acid or alkali that does not easily dissolve the solar cell constituent materials such as the transparent electrode, the semiconductor layer and the lower electrode, or a solution containing a metal salt thereof is used. . As the metal salt, the metal constituting the salt has a negative standard electrode potential,
A salt whose hydrogen overvoltage value is smaller than the absolute value of the standard electrode potential is used. The electrodeposition coating is diluted with deionized water and used, but the solid content is 1 as a range of good film forming property.
% To 25% is preferable. In addition, the conductivity of the electrodeposition liquid is 100 μS / so that the resin is stably suspended, electrophoresis is likely to occur, and deposition is likely to occur at a desired defect portion.
It is preferably in the range of cm to 2000 μS / cm.

The deposited electrodeposited film is required to be unaffected by these treatments if there is a step of using a solvent or heat treatment after electrodeposition, depending on the method of manufacturing the solar cell. Further, the defective portion of the solar cell is a portion that does not contribute to power generation itself, but even when the electrodeposition film is selectively deposited, the area is larger than the substantial area of the defective portion. Therefore, it is desirable that the electrodeposition paint is a light-transmissive material so as not to prevent light from entering a normal portion. Considering the environment when used outdoors as a solar cell, it is required to have good weather resistance and stability to heat, humidity and light. In addition, when the solar cell is used, the solar cell may be bent or impacted depending on the case, so it is necessary to have both mechanical strength and peel strength. The thickness of the electrodeposited coating film is selected appropriately depending on the type of resin because it is preferable that electrical insulation and moisture resistance are maintained, and that light transmission is not impaired. Is 0.1 μm to 50 μm
The place is appropriate.

The electrodeposition resin is roughly classified into anion type and cation type resins. In the present invention, both can be preferably used, but the cation resin has higher rust prevention and throwing power than the anion resin, and the stability and control of the electrodeposition resin coating are easy. Here, rust prevention generally refers to the rust preventive effect of a metal plate, etc.
It can be said that the material has a low permeability to moisture, water vapor, or metal ions, and is excellent in electrical insulation. Further, the throwing power is a parameter indicating how much a coating film is formed on a substrate having a complicated shape and having a uniform thickness, and is also called throwing power. As the throwing power is higher, the electrodeposition resin having a certain thickness is coated even on the minute defect portion of the solar cell. Even when the electrodeposition paint is contaminated, the metal elution of the electrode on the substrate side, which is seen in the anion resin, is not in the cation resin and the paint control is easy. Furthermore, since there is no elution of the metal, there is no concern that metal ions will be mixed in the resin deposited on the substrate, and higher transparency and better electrical insulation can be expected.

As the skeleton resin of the electrodeposition resin, a generally known resin can be used. As the skeleton resin of the electrodeposition resin having insulation and moisture resistance, acrylic resin, epoxy resin, fluororesin, It is appropriately selected from urethane resin and polybutadiene resin as desired. Alternatively, it is possible to use two or more of the above resins in combination in order to improve weather resistance, moisture resistance, flexibility, adhesion, reactivity, and cost. In order to cause these resins to electrophoretically deposit on the solar cell side, it is necessary to introduce a functional group that causes ionization in water and deposits on the solar cell side.

In the case of a cationic resin, the functional group is generally an amino group. Quaternary phosphate, quaternary sulfate, 4
A functional group such as a quaternary ammonium carboxylate may be used. Further, in the case of an anionic resin, a carboxyl group can be mentioned.

Examples of the cationic resin include dimethylaminoethyl methacrylate, triethylaminomethacrylate, amino group-containing (meth) acrylate represented by quaternized amine-containing (meth) acrylate, methyl methacrylate, 2-ethylhexyl methacrylate, and styrene. It can be obtained by copolymerizing with a base monomer such as and neutralizing with an acid. In the case of an epoxy resin, there is a method of introducing a cation group by reacting a polyglycidyl ether represented by epichlorohydrin / bisphenol A type epoxy resin with a primary, secondary or tertiary amine. Next, a method of neutralizing with an organic acid to make it hydrophilic or water-soluble is used. The primary amine can extend the chain length of two epoxy groups, and in the case of the secondary amine, it is added to the terminal epoxy group. Examples of the primary amine include monoethanolamine, examples of the secondary amine include diethylamine, diethanolamine, and examples of the tertiary amine include trimethylamine, triethylamine, tribrutylamine and the like. In the case of a cation type fluororesin, it can be obtained by copolymerizing with a partially fluorinated (meth) acrylate similarly to the acrylic resin. In the urethane resin, a part of the chain extension of polyether diol, polyester diol and tolylene diisocyanate (TDI), methylene di (phenyl isocyanate) (MDI) (isocyanate-terminated urethane resin) has 1, There is a method of adding a secondary or tertiary amine. In the polybutadiene resin, a cationic electrodeposition resin is synthesized by adding 1,2 or tertiary amine to mylenized polybutadiene and epoxidized polybutadiene.

In order to further improve heat resistance, it is preferable to crosslink the cationic electrodeposition resin. A functional group capable of causing a crosslinking reaction is appropriately introduced into the skeleton resin or the side chain. Specific examples thereof include compounds having an epoxy group, a (blocked) isocyanate group, an N-methylol group, a vinyl group and the like. Alternatively, a cross-linking agent (epoxy group, low-molecular compound containing (blocked) isocyanate group, melamine, polyfunctional (meth) acrylate, triallyl isocyanurate) can be used in combination. In some cases, a catalyst may be added to accelerate the crosslinking reaction.
The crosslinking temperature may be appropriately determined, but is generally 100 to 1
80 ° C. is preferred.

In the anionic resin, the carboxyl group is introduced as described above, and the resin is electrophoresed and deposited on the anode side. Furthermore, in order to cure the electrodeposition resin, a curing agent is added, but melamine crosslinking by methylolated melamine,
By introducing styrene or butadiene into the side chain, carbon-
Oxidative polymerization using carbon double bond (> C = C <), and other blocked isocyanate groups (ROCONH
Those using the urethane bond of −) are used.

As described above, the skeleton resin of the electrodeposition resin having insulation and moisture resistance is appropriately selected from acrylic resin, epoxy resin, urethane resin, polybutadiene resin and the like as desired. Considering the environment in which the battery is used, it is desirable that the battery has some heat resistance. That is, the glass transition temperature is preferably 100 ° C. or higher. If the temperature is lower than 100 ° C., even if the above resin is used, there is a concern that the resin may soften or the electrical insulation of the resin may be deteriorated on the midsummer day outdoors. As a method of making the soft resin have a glass transition temperature of 100 ° C. or higher, whether to introduce a hard segment (shorten when the phenyl group or the side chain is an alkyl group) or the like into the skeleton resin, or to increase the symmetry of the skeleton resin molecule , Increasing the amount of the cross-linking agent, and the like.

Next, the grid electrode 107 is formed on the semiconductor layer 10.
It is an electrode for taking out the electromotive force generated at 3, 104, 105 and is called a collecting electrode. The grid electrode 10
Although the suitable arrangement of 7 is determined by the size of the sheet resistance of the semiconductor layer 105 or the upper electrode 106, it is formed in a substantially comb shape and designed so as not to interfere with the incidence of light as much as possible. The grid electrode is required to have a low specific resistance and not become a series resistance of the solar cell, and the desired specific resistance is 10 ^-2.
Ωcm to 10 ⁻⁵ Ωcm, and the material of the grid electrode is Ti, Cr, Mo, W, Al, Ag, Ni, C.
Metallic materials such as u and Sn and powders of metals such as Ag, Pt, Cu and C or alloys thereof, and a polymer binder,
A so-called conductive paste that is made into a paste by mixing the binder solvent in an appropriate ratio can be used.

The bus bar 108 used in the present invention
Is an electrode for further collecting the current flowing through the grid electrode 107 at one end. Ag, Pt, C as electrode materials
It is possible to use a metal such as u, C, or an alloy thereof, and as a form, a wire-shaped or foil-shaped one may be stuck, or the same conductive paste as the grid electrode 107 may be used. As the foil-shaped material, for example, a copper foil, or a copper foil plated with tin, and an adhesive-attached material may be used in some cases.

The solar cell produced as described above is modularized by encapsulation by a known method in order to improve weather resistance and maintain mechanical strength when used outdoors. Specifically, as an encapsulation material, for the adhesive layer, adhesiveness with solar cells, weather resistance,
EVA (ethylene vinyl acetate) in terms of buffering effect
Is preferably used. Further, in order to further improve the moisture resistance and the scratch resistance, a fluorine resin is laminated as the surface protective layer. Examples of the fluorine-based resin include a polymer of tetrafluoroethylene TFE (such as Teflon manufactured by DuPont), a copolymer of ethylene tetrafluoride and ethylene ETFE (such as Tefzel manufactured by DuPont), and polyvinyl fluoride (Tedlar manufactured by DuPont). , Polychlorofluoroethylene CTFE (Neotron manufactured by Daikin Industries, Ltd.) and the like. The weather resistance may be improved by adding an ultraviolet absorber to these resins.

The method for manufacturing the solar cell of the present invention will be described below. In the manufacturing method of the present invention, electrodeposition may be performed after semiconductor formation or after electrode formation. From the viewpoint of long-term stability of solar cell characteristics, it is preferable to perform electrodeposition after forming to reveal latent defects. Furthermore, when electrodeposition is performed after forming the electrodes,
It is more preferable to perform electrodeposition after removing the electrode in the defective portion or increasing the resistance by passivation or the like.

In the solar cell manufacturing method of the present invention, the semiconductor layers 103, 104, 105 and the lower electrode 102, the upper electrode 106, the grid electrode 107, the bus bar 108, etc. are formed by a generally known method. .

As the film forming method of the amorphous silicon semiconductor layer, vapor deposition method, sputtering method, RF plasma CVD method,
Microwave plasma CVD method, ECR method, thermal CVD method,
A known method such as the LPCVD method is used as desired. As an industrially adopted method, an RF plasma CVD method of decomposing a source gas with plasma and depositing it on a substrate is preferably used. Furthermore, RF plasma CVD
While the decomposition efficiency of the raw material gas is as low as about 10% and the deposition rate is slow at about 1Å / sec to about 10Å / sec, it is possible to use a microwave plasma CVD method that improves this point. it can.

In the case of polycrystalline silicon, molten silicon is formed into a sheet, and in the case of CuInSe ₂ / CdS, it is formed by a method such as electron beam evaporation, sputtering, or precipitation by electrolytic decomposition of an electrolytic solution.

A batch type apparatus or a continuous film forming apparatus can be used as a reaction apparatus for carrying out the above film formation, if desired.

As a method of manufacturing the lower electrode, a method such as plating, vapor deposition or sputtering is used. As a method for manufacturing the upper electrode, a resistance heating vapor deposition method, an electron beam heating vapor deposition method, a sputtering method, a spray method, or the like can be used, and is appropriately selected as desired.

The defects of the solar cell are not so obvious that they cause a short circuit or a shunt, and because of their lightness, they do not pose a problem in the initial stage, and there are potential defects that pose a problem during long-term use. In order to effectively perform the passivation and the electrodeposition in the post-process for such defects, a so-called forming process for revealing the defects in advance is necessary. Such a forming process can be specifically achieved by applying an appropriate voltage to the solar cell, and a voltage in the range of about 2V to 20V is used. The polarity can be effectively formed by applying a reverse bias to the solar cell, but a method of reversing the polarity may be used. Examples of the forming device include a device as shown in FIG. In the figure, 401 is a stage, 402 is a solar cell, 403 is a conductive brush, 404 is a rail, 405 is a power source, and 406 is a conducting wire.

As a method for selectively removing (passivating) the upper electrode made of the transparent conductive oxide, a known method can be used, for example, US Pat. No. 4,729,
The method disclosed in Japanese Patent Publication No. 970 is used.

An example of an apparatus suitable for performing such passivation is shown in FIG. In FIG. 9, 302 is an electrolytic solution, 303 is a counter electrode, 304 is a substrate, 305 is all layers up to the upper electrode 106, 306 is a power source, and 307 is a conducting wire. As the electrolyte, AlCl ₃ , ZnCl ₂ , Sn
A Lewis acid such as Cl ₂ , SnCl ₄ or TiCl ₄ is preferably used, and the concentration of the electrolyte is determined in relation to the passivation rate, and usually 0.1% to 10% is preferable. As electrolysis conditions, the voltage is from 2V to 10
The range of V is preferable, and the electrolysis time is determined to be a suitable range in relation to the voltage and the concentration of the electrolytic solution, but the range of 1 second to 30 seconds is preferable.

In the step of selectively depositing the electrodeposition resin on the defective portion, the solar cell having the defective portion and the counter electrode are immersed in the electrodeposition coating material, and a voltage is applied between the solar cell and the counter electrode. It is performed by applying and depositing an electrodeposition resin on the defective portion. When a voltage is applied to the solar cell, it may be applied to a conductive substrate. As the material of the counter electrode, it is required that it is not corroded in the electrodeposition coating, and corrosion-resistant platinum, carbon, nickel, stainless steel or the like is preferably used. Further, the area of the counter electrode is required to have a constant ratio with respect to the area of the solar cell in order to make electrodeposition uniform. As a so-called polar ratio, the solar cell area and the counter electrode are Area ratio is 1/2 to 2/1
It is preferably in the range of. Further, the distance between the solar cell and the counter electrode is an important factor for maintaining the uniformity of electrodeposition, but a suitable range depending on various conditions such as the electrical conductivity of the electrodeposition coating and the applied voltage. Yes Generally 10 mm
To 100 mm is desirable. Since the electrodeposition film is selectively deposited only on the defective portion of the solar cell, it is not preferable to expose the conductive portion such as the substrate in the electrodeposition coating, and therefore,
It is desirable to cover the surface of the conductive substrate, which is the back surface of the solar cell on the light incident side, with an insulating coating material such as a plastic film or a rubber magnet. Further, when the solar cell is irradiated with light, the normal portion other than the defective portion has a low resistance due to the photovoltaic power, so that the relative ratio of the resistance value of the defective portion and the resistance value of the normal portion becomes small and the selectivity becomes low. . Therefore, if desired, the desired selectivity can be achieved by electrodeposition in the dark.

The electrodeposition can be performed by a constant voltage method or a constant current method. For example, in the constant voltage method, the voltage applied to the solar cell is calculated from the electrode potential defined by the Nernst equation. A voltage higher than the hydrogen generation potential, specifically,
A voltage of 2 volts or more, which is a value obtained by adding an overvoltage to the theoretical decomposition voltage of water, is required. Furthermore, since the preferred applied voltage range is different when the conductivity of the electrodeposition paint and the polarity of the voltage applied to the solar cell are reverse bias and forward bias, the configuration, area, and electric power of each solar cell are different. The suitable voltage range is determined from various points such as the physical properties such as the conductivity of the coating material and the polarity of the applied voltage.
It is in the range of 00V. In addition, since a part of the applied voltage is also applied to the solar cell, in the case of a polarity such that the solar cell is reverse biased, a voltage within a range in which the solar cell does not break down. There must be. On the other hand, when the polarity is such that it becomes a forward bias with respect to the solar cell, the forward current of the solar cell flows, resulting in poor selectivity, and in consideration of this point, the voltage must not impair the selectivity. I have to. Specifically, it is preferable that the forward current of the solar cell is not more than twice the shunt current. If it is more than twice, the selectivity of electrodeposition is lost and the electrodeposition resin is deposited also on the outside of the defective portion, so that the current collecting efficiency of the grid electrode is lowered.

In the electrodeposition by the constant current method, the current density is preferably 0.1 to 10 A / d in order to form a dense electrodeposition film depending on the degree of shunt of the solar cell.
It is in the range of m ² .

In any of the constant voltage method and the constant current method described above, the method of determining the end point of electrodeposition may be a method based on time, a method based on Coulomb amount, or the like. Since the electrodeposition coating film has a high resistance, no film is formed on that part when the film thickness reaches a certain value.Therefore, depending on the configuration of the solar cell, electrodeposition will automatically end when a defective part is deposited. However, it is possible for the current to stop flowing. However, in the case where a forward bias is applied to the solar cell, even if there is selectivity at the initial stage of electrodeposition, deposition also occurs in a normal portion with the passage of time. It is necessary to manage the electrodeposition end point by the amount. As the apparatus for performing the above-mentioned electrodeposition step, for example, the apparatus used for passivation shown in FIG. 9 is preferably used. In this case, 302 may be used as the electrodeposition liquid.

In the above description, the solar cell is in the form of a cut sheet, and the passivation and electrodeposition processes are single-wafer processing, but roll-to-roll processing may be performed if necessary. An electrodeposition apparatus suitable for roll-to-roll processing is shown in FIG. FIG. 12 shows an apparatus for continuously performing passivation and electrodeposition. 5 in the figure
01 is a substrate, 502 is a substrate feeding roller, 503 is a substrate winding roller, 504 and 514 are electrolytic baths, 50
5, 515 is a cleaning tank, 506, 516 are drying ovens, 50
7, 517 is a power source, 508, 518 are mask film feeding rollers, 509, 519 are mask film take-up rollers, 510, 520 are mask films, 51
1, 521 is a counter electrode and 512, 522 are conductive rollers. In this preferred embodiment shown in this figure, the solar cell is nip type amorphous silicon deposited on a stainless substrate, and an ITO upper electrode is formed on the light incident side. The solar cell substrate 501 is delivered from a delivery roll 502, immersed in an electrolytic bath 504, passed through a cleaning bath 505 and a drying furnace 506, and then wound up on a winding roll 503. Before being immersed in the electrolytic cell 504, the film 510 for the solar cell backside mask is sent out from the plastic film roll 508 and bonded to the backside of the solar cell substrate 501. After the electrodeposition is completed, it is peeled off again, washed and dried, and then the winding roller 509 is used.
To be wound up. A conductive roller 512 in contact with the solar cell substrate 501 and the counter electrode 5 immersed in the electrolytic cell 504.
The voltage of the power supply 507 is applied between the power supply terminal 11 and the terminal 11.

Since the grid electrode 1007 is formed in a comb shape, the forming method is a sputtering method using a mask pattern, a resistance heating method, a CVD method, or a method in which a metal layer is deposited on the entire surface and then etched and patterned. There are a method of directly forming a grid electrode pattern by photo CVD, a method of forming a negative pattern mask of the grid electrode pattern and then forming, a method of printing a conductive paste, and the like. In the screen printing method, a conductive paste is used as a printing ink by using a screen in which a mesh made of polyester or stainless steel is subjected to desired patterning, and the electrode width can be set to about 50 μm at the minimum. A commercially available screen printing machine is preferably used as the printing machine. The screen-printed conductive paste is heated in a drying oven to crosslink the binder and volatilize the solvent.

As a method of forming the bus bar 108, a metal wire may be fixed with a conductive adhesive, a copper foil may be attached, or the same as the grid electrode 107. As a method of encapsulation, it is desirable to use a commercially available device such as a vacuum laminator to heat and pressure bond the solar cell substrate and the resin film in vacuum.

[0068]

EXAMPLES Hereinafter, the structure of the solar cell of the present invention and the method for manufacturing a solar cell of the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 A solar cell 100 having the layer structure shown in FIG. 3 was produced as follows. First, a substrate made of SUS430BA that has been thoroughly degreased and washed (30 cm x
(30 cm, thickness 0.2 mm) 101 is put in a DC sputtering device (not shown) to deposit 2000 liters of Cr, and the lower electrode 10
Formed 2. The substrate 101 is taken out and put in an RF plasma CVD film forming apparatus (not shown), and the n layer 103, i layer 104,
Deposition was performed in order of the p layer 105. Then, it is placed in a resistance heating vapor deposition device (not shown) and 1 × 10 5 is introduced while introducing oxygen.
^While keeping the internal pressure at ^-4 Torr, an alloy of In and Sn was vapor-deposited by resistance heating, and 700 Å of transparent ITO upper electrode 106 having a function also as an antireflection effect was deposited.

Next, the back surface side of the substrate 101 was covered with an insulating film made of plastic so as to prevent the back surface of the substrate 101 from being electrodeposited at the time of electrodeposition, and was immersed in the electrolytic bath of FIG. As the counter electrode 303, a SUS304 stainless plate having a size of 30 cm × 30 cm so that the polar ratio was 1: 1 and the back side of which was sealed with an insulating film made of plastic was used. Electro-deposition paint 3
For No. 02, an acrylic anionic electrodeposition paint having a solid content of 10% was used. Apply a voltage of + 10V to the substrate 304
It was held for a second and electrodeposition was performed. Solar cell 100 in electrolyzer 3
01, wash thoroughly with pure water, wash away unreacted electrodeposition paint, put in an oven at 50 ° C., and
It was left to dry for a minute. After that, the temperature of the oven is raised at a rate of 10 ° C / min, and after reaching 180 ° C, 3
It was held for 0 minutes to cure the electrodeposition resin. Then the substrate 10
After removing 1 from the oven and cooling, a part of the substrate 101 was cut out and observed with a scanning electron microscope.
Hemispherical deposits 110 having a diameter of about 5 μm to 50 μm were scattered on the surface of 06. When the infrared absorption of this portion was analyzed by using FTIR with a microscopic function, it was confirmed that there was carbonyl group absorption and the electrodeposition coating material was deposited. Further, when an OBIC (optical excitation current microscope) image of this sample was observed, it was confirmed that only the deposited portion of the electrodeposition coating did not generate power, and therefore the deposited film was deposited only on the shunt portion. Furthermore, the area where the electrodeposition resin was deposited was 10 times or less the area of the shunt portion, and there was almost no deposition of the electrodeposition film on the unnecessary portion.

Next, the substrate 101 was placed on a screen printer (not shown), and grid electrodes 108 having a width of 100 μm and a length of 8 cm were printed at intervals of 1 cm. At this time, the conductive paste is 70 parts of Ag filler and 3 parts of polyester binder.
A composition containing 0 part (volume ratio) and 20 parts of ethyl acetate as a solvent was used. After printing, the substrate 101 was placed in an oven and kept at 150 ° C. for 30 minutes to cure the conductive paste.

Further, a bus bar 109 of copper foil with an adhesive having a width of 5 mm was adhered to produce a 30 cm square single cell shown in FIG. Further, ten samples were prepared by the same method.

Next, encapsulation of these samples was carried out as follows. EVA is laminated on the upper and lower sides of the substrate 101, and the fluororesin film ETFE is formed on the upper and lower sides of the EVA.
After stacking (ethylene tetrafluoroethylene) (product name Tefzel manufactured by DuPont), the mixture was put into a vacuum laminator and held at 150 ° C. for 60 minutes to carry out vacuum lamination.

The initial characteristics of the obtained sample were measured as follows.

First, the voltage-current characteristics of the sample were measured, and the shunt resistance was obtained from the slope near the origin. The shunt resistance was 6.5 KΩcm ^{2 to} 13.0 KΩcm ² , and the variation was small. .

Next, the solar cell characteristics were measured using a pseudo solar light source (hereinafter referred to as a simulator) having a light amount of 100 mW / cm ^{2 in} the AM1.5 global sunlight spectrum, and the conversion efficiency was obtained. It was 1% ± 0.5%, which was a good characteristic with little variation.

The reliability test of these samples was conducted according to the temperature and humidity cycle test A defined in the environmental test method and the durability test method of the crystalline solar cell module of Japanese Industrial Standard C8917.
-2.

First, the sample is placed in a thermo-hygrostat whose temperature and humidity can be controlled, and from -40 ° C to + 85 ° C (85% relative humidity).
The cycle test of changing to 10 was repeated 10 times. Next, when the solar cell characteristics of the sample after the test were measured using a simulator as in the initial stage, the average conversion efficiency was 2% lower than the initial conversion efficiency, and no significant deterioration occurred.
When the shunt resistance was measured, there was no significant deterioration with an average decrease of about 10%.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and high reliability.

(Comparative Example 1) Next, for comparison, a solar cell having the same structure as in Example 1 but not subjected to electrodeposition was prepared as follows.

Similar to Example 1, the upper electrode 106 was formed on the substrate 101. Next, the grid electrode 107 was printed in the same manner as in Example 1. Further, copper foil with an adhesive was laminated as the bus bar 108, and 10 single cells of 30 cm square shown in FIG. 8 were produced. Next, encapsulation of this sample was performed in the same manner as in Example 1.

When the initial characteristics of the obtained sample were measured by the same procedure as in Example 1, the conversion efficiency was 3.8 to 5.2.
%, The shunt resistance was 0.5 KΩcm ^{2 to 5} KΩcm ² , and the shunt resistance was low as compared with Example 1, and therefore the conversion efficiency was low.

Next, the reliability test of this sample was evaluated in the same manner as in Example 1. When the solar cell characteristics of the sample after the temperature / humidity cycle test were measured, the average value was decreased by 30% from the initial value, and significant deterioration occurred. Further, the shunt resistance was measured, and it was found that the average shunt resistance decreased by 85%, and shunt was generated after the reliability test.

The shunt portion of this sample was confirmed as follows. First, a reverse bias of 1.5 V was applied to the sample. At this time, current flows through the shunt portion to generate heat, but the normal portion does not generate heat due to the reverse bias because no current flows. When the surface of the sample was observed with an infrared camera in this state, a heat generating part was observed and it was found that the sample electrode was shunted under the grid electrode 107.

Example 2 A solar cell having the structure shown in FIG. 3 was produced by a process of passivating and then electrodeposition. First,
A substrate made of SUS430BA (30 cm ×
(30 cm, thickness 0.2 mm) 101 on the lower electrode 102
After that, it was placed in an RF plasma CVD film forming apparatus (not shown), and the n layer 103, the i layer 104, and the p layer 105 were deposited in this order. As in the case of Example 1, 700 Å of transparent upper electrode 106 having a function also serving as an antireflection effect was deposited.

Next, 10% Al was placed in the electrolytic cell 301 of FIG.
The substrate 101 was filled with a Cl ₃ solution, the back side of the substrate 101 was covered with an insulating film made of plastic, and the substrate 101 was immersed in an electrolytic bath 301. A voltage of -4 V was applied to the substrate 101 side and held for 3 seconds. In this step, the ITO on the shunt portion was removed. After washing, it was dried, and then electrodeposition was performed using the fluorine-based anion electrodeposition coating material 302. It was thoroughly washed with pure water, and the electrodeposition resin was cured in an oven. Then, the substrate 101 is taken out from the oven and cooled, and then the grid electrode 1
07 was formed by screen printing, and a bus bar 108 of copper foil with an adhesive was further laminated to produce a 30 cm square single cell shown in FIG. 8. Similarly, ten samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 6.4% ±
0.8%, the shunt resistance is 55 KΩcm ^{2 to} 12
It was 0 KΩcm ² and had good characteristics with little variation.

Next, a reliability test of this sample was conducted in the same manner as in Example 1. When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, it was 3% lower than the initial value, and significant deterioration did not occur. When the shunt resistance was measured, there was almost no change.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 3 A solar cell was manufactured in the following manner by a method substantially similar to that of Example 2 except that the solar cell of FIG. 4 was used as the solar cell. First, substrate 1
01, a lower electrode 102 composed of an AlSi layer having a texture structure and a ZnO layer as a high resistance transparent conductive member for shunt prevention is formed, and then placed in a microwave plasma CVD film forming apparatus (not shown) to form an n layer 103 , I-layer 10
4 and p layer 105 were deposited in this order to form a bottom layer.
At this time, the i layer 104 was a-SiGe. Next, n layer 11
3, the i layer 114 and the p layer 115 were deposited in this order to form a middle layer. The i layer 114 is made of a-SiG as in the bottom layer.
e. Next, the n layer 123, the i layer 124, and the p layer 125 were deposited in this order to form a top layer. The i layer 124 is a-
It was set to Si. Next, as in Example 1, a transparent upper electrode 106 having a function also serving as an antireflection effect was deposited at 700 Å. In ₂ O ₃ (IO) was used as the upper electrode 106.

Next, passivation was carried out in the electrolytic cell 301 of FIG. 9, washing and drying were carried out, and then an electrodeposition treatment was carried out using the fluorinated anion electrodeposition coating material 302. Then, it was washed and cured. The grid electrode 107 is printed, and the bus bar 108 is further laminated, and 30c shown in FIG.
An m-square triple cell was prepared. Similarly, ten samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 7.5% ±
0.5% and shunt resistance is 35KΩcm ^{2 to} 90K
It was Ωcm ² and had good characteristics and little variation.

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

The solar cell characteristics of the sample after the temperature / humidity cycle test were measured and found to be about 1.5% on average with respect to the initial value.
There was no significant deterioration. When the shunt resistance was measured, there was almost no change.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 4 A solar cell having the structure shown in FIG. 3 was produced by the steps of forming, passivating, and electrodeposition.

First, the lower electrode 102, the n layer 103, the i layer 104, and the p layer 105 are formed in this order on the substrate 101 in the same manner as in Example 1, and then the transparent upper electrode having a function also as an antireflection effect. (ITO) 106 was deposited at 700 liters. Next, the solar cell 100 was formed using the forming apparatus shown in FIG. First, the substrate 101 was set on the stage 401, and −10 V was applied to the conductive brush 403 by the power supply 405, and the conductive brush 403 was swept along the rail 404 at a speed of 5 mm / sec.

Next, as in Example 1, the electrolytic cell 30 shown in FIG.
1 was filled with a 10% AlCl ₃ solution and the back side of the substrate 101 was covered with an insulating film made of plastic and immersed in an electrolytic bath 301. A voltage of -4 V was applied to the substrate 101 side and held for 3 seconds. In this step, the ITO on the shunt portion was removed.

After washing, drying was carried out, and then an electrodeposition treatment was carried out using the fluorinated anion electrodeposition coating material 302. It was thoroughly washed with pure water, and the electrodeposition resin was cured in an oven. After that, the substrate 101 was taken out from the oven and cooled, and then the grid electrode 107 was formed and the bus bar 108 was further laminated thereon to fabricate a single cell of 30 cm square shown in FIG.
Similarly, ten samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 6.4% ±
1.2%, the shunt resistance is 105 KΩcm ² to 2
It was 50 KΩcm ² and had good characteristics and little variation.

Next, the reliability test of this sample was performed in the same manner as in Example 1. When the solar cell characteristics of the sample after the temperature-humidity cycle test were measured, it was 3% lower than the initial value.
No significant deterioration occurred. When the shunt resistance was measured, there was almost no change.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 5 A solar cell having the structure shown in FIG. 5 was manufactured in substantially the same manner as in Example 1.

First, on a 30 cm square glass substrate (7059 made by Corning) 101, an S vapor deposition apparatus (not shown) was used.
A transparent top electrode 106 of nO ₂ was deposited. Then, the upper electrode 106 was patterned by etching so that subcells having a width of 2 cm were arranged side by side with a gap having a width of 5 mm. Next, the upper electrode 10 is formed using a metal mask.
P layer 105, i layer 104, n so as to substantially overlap 6
Layer 102 was deposited. Next, the substrate 101 was immersed in the electrolytic bath 301 and subjected to electrodeposition treatment using a cationic electrodeposition coating material. Further, the substrate 101 was put into a sputtering apparatus (not shown) using a metal mask to form an aluminum lower electrode, and a 10-cell series 30 cm square single cell was produced. Ten samples were manufactured by the above manufacturing method.

The initial characteristics of the obtained sample were that the conversion efficiency was 6.0% ± 1.0% and the shunt resistance was 35 KΩcm ² 〜.
It was 90 KΩcm ² and had good characteristics with little variation.

Next, the reliability test of this sample was evaluated in the same manner as in Example 1. When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, it was 3% lower than the initial value, and no significant deterioration occurred. The shunt resistance was measured and found to be about 4% lower.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 6 A solar cell 100 having the structure shown in FIG. 3 was produced in the same manner as in Example 1 except that the electrodeposition was performed after forming the p layer 105.

As in Example 1, the lower electrode 102 was formed on the substrate 101 made of SUS430BA, and the n layer 103, the i layer 104, and the p layer 1 were formed by an RF plasma CVD film forming apparatus (not shown).
Deposition was performed in the order of 05.

Next, as in the first embodiment, the substrate 101 described above is used.
The back side of was covered with an insulating film made of plastic and immersed in the electrolytic bath 301 of FIG. Electrodeposition treatment was performed using the styrene-based anion electrodeposition coating material 302. It was thoroughly washed with pure water, and the electrodeposition resin was cured in an oven. After that, the substrate 101 was taken out from the oven and cooled, and then 700 Å of transparent upper electrode 106 having a function also serving as an antireflection effect was deposited in the same manner as in Example 1. Then the grid electrode 1
07 and the bus bar 108 were laminated to produce a 30 cm square single cell shown in FIG. Similarly, ten samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 6.4% ±
l. 5% and the shunt resistance is 10 KΩcm ² to 50
It was KΩcm ² and had good characteristics.

Next, the durability characteristics of this sample were evaluated in the same manner as in Example 1. When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, it was 2% lower than the initial value, and significant deterioration did not occur. When the shunt resistance was measured, there was almost no change.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 7 A solar cell having the layer structure shown in FIG. 3 was produced as follows. First, in the same manner as in Example 1, a Cr lower electrode, n was formed on the SUS430BA substrate 101.
Layer 103, i layer 104, p layer 105 and ITO top electrode 106 were deposited.

Next, referring to FIG. 9, the back side of the substrate 304 is covered with an insulating film made of plastic to form an electrodeposition tank 30.
It was immersed in 1. As the counter electrode 303, SUS with a size of 30 cm × 30 cm so that the polar ratio is 1: 1 and the back side is sealed with an insulating film made of plastic.
A 304 stainless plate was used. As the electrodeposition coating material 302, an acrylic kaolin-based electrodeposition coating material (acrylic clear A-7X manufactured by Uemura Kogyo Co., Ltd.) having a solid content of 10% was used. Board 3
A voltage of -10 V was applied to 04 and held for 10 seconds for electrodeposition. The solar cell 100 was pulled up from the electrodeposition tank, thoroughly washed with pure water, the undeposited electrodeposition coating was washed off, placed in an oven at 50 ° C., and left for 30 minutes to dry the water. After that, the temperature of the oven was increased at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 30 minutes to cure the electrodeposition resin. After that, the solar cell 100 was taken out of the oven, after cooling, a part of the solar cell was cut out and observed with a scanning electron microscope. On the surface of the upper electrode 106, hemispherical deposits with a diameter of about 5 μm to 50 μm were spotted. Was observed there. Infrared absorption of this part is
It was confirmed by TIR analysis that the carbonyl group of the acrylic ester was absorbed and the electrodeposition paint was deposited. Further, by observing the OBIC image of this sample, it was confirmed that only the deposited portion of the electrodeposition paint did not generate power, and the deposited film was deposited only on the shunt portion. Furthermore, it was also confirmed that, on average, the area was deposited about 7 times the area of the shunt portion. Next, in the same manner as in Example 1, the grid electrode 107 and the bus bar 108 are formed, and 3
A 0 cm square single cell was prepared. Ten samples were prepared by the same method. Further, encapsulation of these samples was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 6.3 ± 0.
The 7% shunt resistance was 15 KΩcm ² ± ² KΩcm ^2, which was a good characteristic with little variation.

The solar cell characteristics after the temperature / humidity cycle test were measured. As a result, the average conversion rate was 2% with respect to the initial conversion efficiency, and no significant deterioration occurred. Moreover, when the shunt resistance was measured, no significant deterioration was observed at a reduction rate of about 10% at the initial stage. It has been found that electrodeposition has a good effect.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and high reliability.

(Embodiment 8) The applied voltage of 10 V during electrodeposition is set to 2
Example 7 except that the energization time was changed from 5 seconds to 10 seconds to 3 seconds
Was prepared in the same manner as in. Ten samples were manufactured by the above manufacturing method.

The initial characteristic of the obtained sample was that the conversion efficiency was 6.
1% ± 0.8%, shunt resistance is 20KΩcm ² ± 3K
Was Ωcm ² .

Next, a reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature and humidity cycle test were measured, the rate of decrease was 1% of the initial value, and no significant deterioration occurred. The shunt resistance was measured and found to be 9%. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability. The ratio of forward current to shunt current of the solar cell during electrodeposition was 3.2. In Example 7, it was 0.6.

Example 9 Acrylic cationic electrodeposition resin (Acrylic Clear A-7X glass transition temperature about 120 ° C. manufactured by Uemura Kogyo Co., Ltd.) was used as an acrylic cationic electrodeposition resin (glass transition temperature about 120 ° C.) with a low crosslinking density. Ten sheets were prepared in the same manner as in Example 7 except that the temperature was changed to 70 ° C. The evaluation of the obtained sample was in accordance with Example 1.

The initial characteristics of the obtained sample are 6.3% ±
0.8%, shunt resistance is 14KΩcm ² ± 2KΩcm
² , which was a good characteristic.

Next, a reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the rate of decrease was 4% of the initial value, and significant deterioration hardly occurred. When the shunt resistance was measured, it was 12% lower than the initial value, and there was no significant deterioration. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Example 10 Acrylic cationic electrodeposition resin (Acrylic Clear A-7X manufactured by Uemura Kogyo Co., Ltd. minimum film forming temperature (about 60 ° C.) was used as an acrylic cationic electrodeposition resin (minimum film forming temperature about 60 ° C.). 10 samples were prepared in the same manner as in Example 7 except that the temperature was changed to 25 ° C.) The evaluation of the obtained sample was in accordance with Example 1.

The initial characteristics of the obtained sample are 6.4% ±
1.5%, shunt resistance is 16 KΩcm ² ± 4 KΩcm
² , which was a good characteristic. However, with this paint, initial characteristics were significantly reduced to 5.0% unless it was washed with water immediately after the completion of electrodeposition.

Then, the reliability test of the sample obtained by sufficiently washing with water was conducted in the same manner as in Example 1. The solar cell characteristics of the sample after the temperature / humidity cycle test were measured, and the rate of decrease was 2% of the initial value, and no significant deterioration occurred. When the shunt resistance was measured, it was 9% lower than the initial value. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Example 11 Acrylic cationic electrodeposition resin (acrylic clear A-7X manufactured by Uemura Kogyo Co., Ltd.) was changed to an epoxy cationic electrodeposition resin (solid content 10% manufactured by Uemura Kogyo Co., Ltd.). Ten samples were prepared in the same manner as in Example 7 except for the above. The evaluation of the obtained sample also followed Example 7.

The initial characteristics of the obtained sample are 5.9% ±
0.9%, shunt resistance is 29 KΩcm ² ± 5 KΩcm
² , which was a good characteristic.

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, it was 2% of the initial value, and the deterioration rate did not cause significant deterioration. When the shunt resistance was measured, it was 11% lower than the initial value. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 12) A procedure was carried out except that the cation type electrodeposition resin of acrylic (Acrylic Clear A-7X manufactured by Uemura Kogyo Co., Ltd.) was changed to the cation type electrodeposition resin of fluorine (Uemura Kogyo Co., Ltd.). Ten samples were prepared in the same manner as in Example 7.
The evaluation of the obtained sample was also in accordance with Example 1.

The initial characteristics of the obtained sample are 6.5% ±
0.7%, shunt resistance is 24 KΩcm ² ± 3 KΩcm
² , which was a good characteristic.

Next, a reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, it was 10% lower than the initial value. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 13) A cationic cationic electrodeposition resin (acrylic clear A-7X manufactured by Uemura Kogyo Co., Ltd.) was treated with a cationized oligomer (polyethylene glycol having a molecular weight of 2200 and modified at both terminals with carboxylic acid (Kawaken Fine Co., Ltd.).
10 samples were prepared in the same manner as in Example 7 except that the reaction product was changed to a cationized epoxy (Wastex manufactured by Nagase Kasei Co., Ltd.). The evaluation of the obtained sample was also in accordance with Example 1.

The initial characteristics of the obtained sample are 6.1% ±
0.6%, shunt resistance is 8 KΩcm ²± 1 KΩcm²
It was a good characteristic. Next, the reliability test of this sample
Was carried out in the same manner as in Example 1. After completion of temperature / humidity cycle test
The solar cell characteristics of the sample of
This is the rate of decrease and no major deterioration occurred. Shunt resistance
When measured, the value was 34% lower than the initial value.
From the results of this example, the solar cell manufacturing method of the present invention
The solar cell of the present invention has a good yield and good characteristics.
It can be seen that the durability is also good.

Example 14 Acrylic cationic electrodeposition resin (acrylic clear A-7X manufactured by Uemura Kogyo Co., Ltd.) was used as an epoxy / polybutadiene cationic electrodeposition resin (RADICOAT N800 black pigment manufactured by Nippon Paint Co., Ltd.). enter)
Ten samples were prepared in the same manner as in Example 7 except that the above was changed to. The evaluation of the obtained sample was also in accordance with Example 1.

The initial characteristics of the obtained sample are 5.8% ±
0.6%, shunt resistance is 15 KΩcm ² ± ² KΩcm
² , which was a good characteristic.

Next, a reliability test of this sample was conducted in the same manner as in Example 1. When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, it was 10% lower than the initial value. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 15) The same procedure as in Example 7 was carried out except that the energization time during electrodeposition was changed from 10 seconds to 3 seconds.

Ten samples were manufactured by the above manufacturing method. Running
With a scanning electron microscope, the area is about 0.5 times as large as the shunt area.
It was confirmed that it had been accumulated. Of the obtained sample
Initial characteristics: conversion efficiency 5.5 ± 1.1%, shunt resistance
Is 8 KΩcm²± 2 KΩcm ²Met.

Next, the reliability test of this sample was conducted in the same manner as in Example 1. When the solar cell characteristics of the sample after the temperature / humidity cycle test were measured, the rate of decrease was 4% of the initial value, and no significant deterioration occurred. Further, the shunt resistance was measured and found to be 17% lower. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Example 16 Next, a solar cell having the structure shown in FIG. 5 was produced in substantially the same manner as in Example 7.

First, a SnO ₂ transparent upper electrode 106 was deposited on a 30 cm square Corning 7059 substrate 101 by using a vapor deposition device (not shown). Then, the upper electrode 106 was patterned by etching so that subcells having a width of 2 cm were arranged side by side with a gap having a width of 5 mm. Next, a p-layer 105, an i-layer 104, and an n-layer 103 were deposited using a metal mask so as to substantially overlap with the upper electrode 106. Next, the substrate 101 was put into a sputtering device (not shown) using a metal mask to form an aluminum lower electrode 102, and a 10-cell series 30 cm square single cell was produced. The electrodeposition method was in accordance with Example 7. Ten samples were manufactured by the above manufacturing method.

The initial characteristic of the obtained sample was that the conversion efficiency was 6.
0% ± 1.0%, shunt resistance is 27KΩcm ² ± 4K
Was Ωcm ² .

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. Also, the shunt resistance was measured and found to be 1% lower. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 17 A polycrystalline solar cell having the structure shown in FIG. 7 was manufactured in substantially the same manner as in Example 7.

As in Example 7, the lower electrode 102 was formed on the SUS430BA substrate (30 cm × 30 cm, thickness 0.2 mm) 101. The substrate 101 is taken out and placed in an RF plasma CVD film forming apparatus (not shown) to form the n layer 103, i
The layer 104 and the p layer 105 were deposited in this order. After that, the substrate 101 was taken out from the oven and cooled, and 700 Å of a transparent upper electrode 106 having a function also serving as an antireflection effect was deposited as in Example 7. Electrodeposition was performed in the same manner as in Example 7, then the grid electrode 107 and the bus bar 108 of copper foil with an adhesive were formed to produce a 30 cm square single cell. Similarly, ten samples were prepared. Further, the encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 6.4% ±
0.8%, shunt resistance is 6 KΩcm ²± 1 KΩcm²
It was a good characteristic. Next, the reliability test of this sample
Was carried out in the same manner as in Example 1.

When the solar cell characteristics of the sample after the end of the temperature / humidity cycle test were measured, the rate of decrease was 10% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, the decrease was 19%. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Comparative Example 17 The same operation as in Example 17 was carried out except that the electrodeposition operation was not performed.

The initial characteristics of the sample are 4.3% ± 1.2%,
The shunt resistance was 0.6 KΩcm ² ± 0.2 KΩcm ² . Compared to Example 17, the shunt resistance was low, and therefore the conversion efficiency was low.

Next, the reliability test of this sample was conducted in the same manner as in Example 1. When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the reduction rate was 32% of the initial value. When the shunt resistance was measured, it decreased by 76%.

Example 18 The following solar cell was produced in substantially the same manner as in Example 7 except that the triple solar cell shown in FIG. 4 was used as the solar cell. First, a lower electrode 102 consisting of a textured AlSi layer and a ZnO layer as a high resistance transparent conductive member for shunt prevention is formed on a substrate 101, and then placed in a microwave plasma CVD film forming apparatus (not shown). n layer 103, i layer 104, p layer 1
Deposition was performed in the order of 05 to form a bottom layer. Then i
The layer 104 was a-SiGe. Next, the n layer 113, the i layer 114, and the p layer 115 were deposited in this order to form a middle layer. The i layer 114 was made of a-SiGe similarly to the bottom layer. Next, the n layer 123, the i layer 124, and the p layer 125 were deposited in this order to form a top layer. The i layer 124 is a-SiG
e. Next, as in Example 1, a transparent upper electrode 106 having a function of also having an antireflection effect was deposited at 700 Å. In ₂ O ₃ (IO) was used as the upper electrode.

Next, the acrylic cationic electrodeposition coating composition used in Example 7 was used for electrodeposition treatment. Then wash,
Cured. The grid electrode 107 was printed, and the bus bar 108 was further laminated to produce a 30 cm square triple cell. Similarly, ten samples were prepared. Further, encapsulation of these samples was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 7.4% ±
0.8%, shunt resistance is 16KΩcm ² ± 2KΩcm
² , which was a good characteristic.

Next, the reliability test of this sample was conducted in the same manner as in Example 1. When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the rate of decrease was 3% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, it was 11% reduction. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Comparative Example 18 The same operation as in Example 18 was carried out except that the electrodeposition operation was not performed.

The initial characteristics of the obtained sample are 4.5% ±
1.8%, shunt resistance is 0.3KΩcm ² ± 0.1K
Was Ωcm ² . The shunt resistance was lower than that in Example 12, and thus the conversion efficiency was low.

Next, a reliability test of this sample was conducted in the same manner as in Example 1. When the solar cell characteristics of the sample after the temperature / humidity cycle test were completed, the reduction rate was 40% of the initial value. When the shunt resistance was measured, it was reduced by 85%.

Example 19 A solar cell having the layer structure shown in FIG. 3 was produced as follows. First, in the same manner as in Example 1, Cr (lower electrode) on the SUS430BA substrate,
An n layer, an i layer, a p layer and ITO (upper electrode) were formed.

Next, the back surface side of the substrate 101 was covered with an insulating film made of plastic and immersed in the electrolytic bath of FIG. 9 so that the back surface of the substrate 101 was not electrodeposited during electrodeposition.

The counter electrode 303 has a size of 30 cm × 30 cm so that the pole ratio is 1: 1 and the substrate 30 is
4 was used a SUS304 stainless steel plate whose back side was sealed with a plastic insulating film. The electrodeposition liquid 302 was an acrylic-melamine-based anion electrodeposition paint having a solid content of 10%, and the electric conductivity was measured using a CM20S manufactured by Toa Denpa Kogyo Co., Ltd., which was 620 μS / cm. When pH was measured using HM-30S, it was 8.47. Bath temperature 25.4
Under the condition that the distance between the electrodes was 50 mm, a voltage of plus 3 V was applied to the substrate 304 and kept for 30 seconds for electrodeposition.
The relationship between the current flowing at this time and the time was as shown in FIG. Further, the total amount of Coulomb of the flowing current was 60 mC. The amount of coulomb was measured by a coulomb meter HF201 manufactured by Hokuto Denko KK. After electrodeposition, solar cell 100
Was quickly removed from the electrodeposition tank, thoroughly washed with pure water, the unreacted electrodeposition paint was washed off, placed in an oven at 50 ° C., and left to stand for 10 minutes to dry the water. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 20 minutes to cure the electrodeposition resin.

A part of the sample thus obtained was cut out and observed with a scanning electron microscope.
On the surface of No. 6, hemispherical deposits having a diameter of about 5 μm to 50 μm were scattered and observed. The infrared absorption of this portion was analyzed by using FTIR with a microscope, and it was confirmed that all samples had absorption of the carbonyl group of the acrylic ester and the electrodeposition coating was deposited. Further, when the OBIC image of this sample was observed, it was confirmed that only the deposited portion of the electrodeposition coating did not generate power, and therefore the deposited film was deposited only on the shunt portion.

Further, similarly to the above-mentioned method, only the voltage during electrodeposition is 5V, 7V, 10V, 15V, 20V, 30V.
A sample was prepared as. Next, in the same manner as in Example 1, grid electrodes and bus bars were formed. FIG. 14 shows the result of measuring the initial characteristics of the sample thus manufactured.

As shown in FIG. 14, the voltage during electrodeposition is 5V.
It turned out that 20V is suitable. Further, the shunt resistance was a favorable value of 50 to 70 KΩcm ^2, and the variation was small.

Then, in the same manner as described above, 10 V,
Electrodeposition was performed for 30 seconds under the condition that the distance between the electrodes was 50 mm. After that, grid electrodes 107 having a width of 100 μm and a length of 8 cm were printed at intervals of 1 cm by the method described above, and copper bus bars with an adhesive having a width of 5 mm were adhered to produce 10 single cells of 30 cm square. Next, encapsulation of these samples was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample were measured by the method described above, and the conversion efficiency was calculated. The average was 6.5% ±
It was 0.5%, and the characteristics were good, and there was little variation.

The reliability test of these samples was conducted in the same manner as in Example 1.

The solar cell characteristics after the test were 5% on average with respect to the initial conversion efficiency, and no significant deterioration occurred. Also, when the shunt resistance is measured, it is about 10%.
There was no significant deterioration in It has been found that electrodeposition has a good effect.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and high reliability.

Example 20 A solar cell having the structure shown in FIG. 3 was manufactured in substantially the same manner as in Example 19 except that the kind of electrodeposition paint and the electrodeposition time were changed.

As in Example 19, a lower electrode, an n-layer, an i-layer, a p-layer and a transparent upper electrode were deposited on a SUS430BA substrate.

Next, as in Example 19, the substrate 101 was used.
The back side of was covered with an insulating film made of plastic and immersed in the electrodeposition tank of FIG. The electrodeposition liquid was an acrylic-melamine-based anionic electrodeposition paint having a solid content of 10.5% and containing a large amount of styrene, and had an electric conductivity of 518 μS / cm and a pH of 8.05. Under the bath temperature of 25.0 ° C., the distance between the electrodes was set to 30 mm, and a voltage of plus 10 V was applied to the substrate 304 for electrodeposition. Electrodeposition was carried out with the completion time of electrodeposition being 10 seconds. After electrodeposition, the solar cell 100 is quickly pulled up from the electrodeposition tank, thoroughly washed with pure water, unreacted electrodeposition paint is washed off, and placed in an oven at 50 ° C.
It was left for 0 minutes to dry the water. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 20 minutes to cure the electrodeposition resin. Next, a grid electrode and a bus bar were formed to prepare a 30 cm square single cell. The obtained sample showed excellent initial characteristics as compared with the single cell of Comparative Example 1. Similar to the method described above, only the electrodeposition time is 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds.
Samples were prepared by changing the time to 70 seconds, 70 seconds, 80 seconds, 90 seconds, and 100 seconds.

When these initial characteristics were measured by the same method as in Example 1, the results shown in Table 1 were obtained. According to Table 1, electrodeposition can be controlled by time and applied voltage 1
It has been found that an electrodeposition time of 30 to 90 seconds is suitable for 0V.

Then, in the same manner as the above-mentioned method, 10V6
After electrodeposition under the condition of 0 seconds, the encapsulation
Solution, 10 samples were prepared. Got
The initial characteristics of the sample are the average conversion efficiency of 6.6% ± 0.4%,
Shunt resistance is 30 kΩcm ²To 75 kΩcm²And
It had good characteristics.

Next, the durability characteristics of this sample were evaluated in the same manner as in Example 1.

When the conversion efficiency of the sample after the completion of the temperature / humidity cycle test was measured, it was found to be 3.2% lower than the initial value and no deterioration occurred. When the shunt resistance was measured, an average reduction of about 8% showed almost no significant deterioration, good characteristics were obtained, and durability was also good. Further, by containing a large amount of a non-functional monomer such as styrene in the electrodeposition resin to be used, a strong electrodeposition resin was laminated and the durability could be increased.

(Example 21) A thin film polycrystalline solar cell having the structure shown in FIG. 7 was prepared in substantially the same manner as in Example 19 by changing the kind of electrodeposition coating material and determining the total Coulomb amount of the current flowing at the end point of electrodeposition. .

First, in the same manner as in Example 19, SUS430B
A substrate (30 cm x 30 cm, thickness 0.2 mm) 10
1. A lower electrode 102 is formed on the first electrode 1 and then an RF (not shown) is formed.
It is put in a plasma CVD film forming apparatus and n layer 103 and i layer 10
Then, the p-layer 105 was deposited in this order. Then, Example 1
In the same manner as above, 700 Å of transparent upper electrode 106 having a function of also having an antireflection effect was deposited.

Next, as in Example 19, the substrate 101 was used.
The back side of was covered with an insulating film made of plastic and immersed in the electrodeposition tank of FIG. The electrodeposition liquid is a dispersion of a fluororesin in an acrylic-melamine-based anion electrodeposition paint having a solid content of 10.2%, and the electric conductivity is 560 μS / cm.
The pH was 7.93. Electrodeposition was performed under a bath temperature of 25.6 ° C. with a distance between electrodes of 50 mm and a voltage of 10 V applied to the substrate 304. The electrodeposition was controlled by the amount of coulomb after energization, and the electrodeposition was terminated when the total amount of coulomb reached 50 mC. It was thoroughly washed with pure water, and the electrodeposition resin was cured in an oven. Next, a grid electrode 107 is printed, and a copper foil bus bar 108 with an adhesive is further laminated, and 30c
An m-square single cell was produced.

When the initial characteristics of the obtained sample were measured by the same method as in the example, the conversion efficiency was 5.60% and the shunt resistance was 9.34 kΩcm ² .

Next, the total coulomb amount is 100 mC, 150 mC, 200 mC, 250 mC, 3 by the same procedure as above.
Electrodeposition was terminated at 00 mC to prepare a sample. Furthermore, when the initial characteristics were measured by the same method as described above, Table 2
It became like. According to Table 2, the total coulomb amount is 100 mC
It was found that it is appropriate to finish the electrodeposition of 200 mC.

Then, after completing the electrodeposition with an applied voltage of 10 V and a total Coulomb amount of 100 mC in the same manner as described above,
Encapsulation of this sample was performed as in Example 1.

When the reliability test of the obtained sample was performed in the same manner as in Example 1, the solar cell characteristics of the sample after the temperature-humidity cycle test were measured, and the average value was decreased by 2% from the initial value and deteriorated. Did not occur. When the shunt resistance was measured, there was almost no change.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

(Example 22) A solar cell having the structure shown in Fig. 3 was produced in the same manner as in Example 19 by a constant current method using an ultraviolet curable coating material.

First, in the same manner as in Example 19, SUS430B
A substrate (30 cm x 30 cm, thickness 0.2 mm) 10
1. A lower electrode 102 is formed on the first electrode 1 and then an RF not shown
The n layer 103 and the i layer 10 were placed in a plasma CVD film forming apparatus.
4, the p layer 105 was deposited in this order. Then, Example 1
In the same manner as in No. 9, 700 Å of transparent upper electrode 106 having a function of also having an antireflection effect was deposited.

Next, as in Example 19, the substrate 101 was used.
The back side of was covered with an insulating film made of plastic and immersed in the electrodeposition tank of FIG. The electrodeposition liquid was an ultraviolet curable acrylic anion electrodeposition coating composition having a solid content of 15.1%, and had an electric conductivity of 1240 μS / cm and a pH of 7.03. At a bath temperature of 25.2 ° C, the distance between the electrodes is 50 mm,
A constant current method was used for electrodeposition, and the current was 0.2 A / dm ² , 0.
5 A / dm ² , 1.0 A / dm ² , 1.5 A / dm ² ,
It was set to 2.0 A / dm ² and each was energized for 10 seconds. At this time, in the constant current method, the voltage tended to increase as the electrodeposition resin was laminated. Since the voltage gradually rises with electrodeposition, it is necessary to manage the voltage so that it is below the breakdown voltage of the solar cell. After sufficiently washing with pure water to wash away the unreacted electrodeposition coating material, the water content was removed, and the deposited coating material was placed in an oven at 80 ° C. and smoothed for 5 minutes in order to smooth the coating material. After that, it is taken out of the oven, cooled, and then irradiated with an ultraviolet irradiation device and an ultra-high pressure mercury lamp for 150
It was cured under the exposure condition of mJ / cm ² . Next, the grid electrode 107 is printed, and the copper foil bus bar 1 with an adhesive is further printed.
08 was laminated to prepare a single cell of 30 cm square.

The initial characteristics of the obtained sample were measured in the same manner as described above. The results are shown in Fig. 15. From FIG. 15, it was found that a suitable current during electrodeposition is 0.5 A / dm ² to 1.5 A / dm ² . After that, electrodeposition current 1.0A /
Ten samples were prepared under the condition of dm ² in the same manner as the above method. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristic of the obtained sample is that the conversion efficiency is 6.2.
% ± 0.8%, which was a good characteristic.

Next, the reliability test of this sample was performed in the same manner as in Example 1. When the solar cell characteristics of the sample after the temperature / humidity cycle test were measured, the average value was 5.3% lower than the initial value, and no deterioration occurred. When the shunt resistance was measured, there was almost no significant deterioration with a decrease of about 10%.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

(Embodiment 23) The structure of the solar cell shown in FIG.
Similar to Example 19 except that the ripple type solar cell was used.
A solar cell was manufactured by the following method. First, the base
Light reflecting layer of AlSi having a texture structure on the plate 101
And the light of high resistance transparent conductive member ZnO for shunt prevention.
A lower electrode 102 having a reflection increasing layer laminated thereon was formed. So
After that, enter a microwave plasma CVD film forming device (not shown).
The n layer 103, the i layer 104, and the p layer 105 are stacked in this order.
A bottom layer was formed. At this time, the i layer 104 is aS
iGe. Next, the n layer 113, the i layer 114, and the p layer 1
The layers were laminated in the order of 15 to form a middle layer. i layer 114
Was a-SiGe as in the bottom layer. Next, n layer 1
23, i layer 124, p layer 125 are stacked in this order
Layers were formed. The i layer 124 was a-Si. afterwards,
Similar to the first embodiment, it has a function that also has an antireflection effect.
A transparent upper electrode 106 was laminated in 700 liters. Upper electrode 1
In as 06₂O ₃(IO) was used.

Next, an electrodeposition treatment was performed using an acrylic-melamine type anion electrodeposition coating material under the conditions of a distance between electrodes of 50 mm, an applied voltage of 10 V and an electrodeposition time of 30 seconds. Then, it wash | cleaned and heat-hardened. After that, the grid electrode 107 was printed, and the bus bar 108 was further laminated to produce a 30 cm square triple cell. Similarly, ten samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 7.6% ±
0.7% and shunt resistance is 50KΩcm ^{2 to} 98K
It was Ωcm ² and had good characteristics and little variation.

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the conversion efficiency was decreased by 4.5% on average from the initial value, and no significant deterioration was observed. Also, the shunt resistance was reduced by 5%, and almost no deterioration was observed.

From this example, it is understood that the solar cell manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 24 A solar cell 100 having the layer structure shown in FIG. 3 was produced as follows. First, a substrate made of SUS430BA that has been thoroughly degreased and washed (30 cm x
(30 cm, thickness 0.2 mm) 101 is put in a DC sputter device (not shown) to deposit Cr 200 Å, and lower electrode 102
Was formed. The substrate 101 is taken out and placed in an RF plasma CVD film forming apparatus (not shown) to form the n layer 103, the i layer 104, and the p layer.
Deposition was performed in order of layer 105.

Next, referring to FIG. 9, the back side of the substrate 301 is covered with a plastic insulating film to form an electrodeposition tank 30.
It was immersed in 1. The counter electrode 303 has a size of 30 cm × 30 cm so that the polar ratio is 1: 1, and the substrate 3
For 04, a SUS304 stainless plate whose back side was sealed with a plastic insulating film was used.
The electrodeposition coating 302 is an acrylic cationic electrodeposition coating having a solid content of 10% (Acrylic Clear A-7 manufactured by Uemura Industry Co., Ltd.).
X) was used. A voltage of -20 V was applied to the substrate 304 and held for 7 seconds for electrodeposition. The solar cell 100 is pulled up from the electrodeposition tank, thoroughly washed with pure water, the undeposited electrodeposition paint is washed off, and placed in an oven at 50 ° C.
It was left for 0 minutes to dry the water. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 30 minutes to cure the electrodeposition resin. After that, the solar cell 100 is taken out of the oven, and after cooling, the solar cell 100 is cooled.
When a part of the above was cut out and observed with a scanning electron microscope, radial deposits having a diameter of about 5 μm to 50 μm were scattered on the surface of the semiconductor layer 105. When the infrared absorption of this portion was analyzed by using FTIR with a microscopic function, it was confirmed that there was absorption of the carbonyl group of the acrylic ester and that the electrodeposition coating was deposited. Furthermore, O of this sample
When the BIC image was observed, it was confirmed that only the deposited portion of the electrodeposition coating did not generate power, and therefore the deposited film was deposited only on the shunt portion. Furthermore, it was also confirmed that the deposit was made over an area about 8 times as large as the shunt portion.

Then, the device was placed in a resistance heating vapor deposition device (not shown), and while introducing oxygen, the internal pressure was adjusted to 1 × 10 ⁻⁴ Torr.
While maintaining the above condition, an alloy of In and Sn was vapor-deposited by resistance heating, and 700 Å of transparent ITO upper electrode 106 having a function also serving as an antireflection effect was deposited. Next, Example 1 was formed on ITO.
Similarly to the above, the grid electrode 107 and the bus bar 108 were formed to produce a single cell of 30 cm square. Ten samples were prepared by the same method. Next, encapsulation of these samples was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 6.5 ± 0.
The characteristic was 6% and the variation was small. Further, the shunt resistance was 17 KΩcm ² ± ² KΩcm ² , which was a good characteristic, and there were few variations.

Next, a temperature / humidity cycle test was performed, and the solar cell characteristics of the sample after the test were measured. The average conversion rate was 2% with respect to the initial conversion efficiency, and no significant deterioration occurred. Further, when the shunt resistance was measured, there was no significant deterioration at the initial reduction rate of about 9%. It has been found that electrodeposition has a good effect.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 25) Example 2 was repeated except that the applied voltage of 20 V during electrodeposition was changed to 30 V and the energization time was changed from 7 seconds to 5 seconds.
It produced like 4th. Ten samples were manufactured by the above manufacturing method.

The initial characteristic of the obtained sample was that the conversion efficiency was 6.
0% ± 0.8%, shunt resistance is 21KΩcm ² ± 2K
Was Ωcm ² .

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. Also, the shunt resistance was measured and found to be 10% lower. From the results of this example, it can be seen that the yield of the solar cell of the present invention manufactured by the method of manufacturing a solar cell of the present invention is good, the characteristics are good and the durability is also good. The ratio of the forward current to the shunt current of the solar cell at the time of electrodeposition was 2.4. In Example 24, it was 0.4.

Example 26 Acrylic cationic electrodeposition resin (Acrylic Clear A-7X glass transition temperature about 120 ° C. manufactured by Uemura Kogyo Co., Ltd.) was used as an acrylic cationic electrodeposition resin (glass transition temperature) having a low cross-linking density. It was produced in the same manner as in Example 24 except that the temperature was changed to about 70 ° C. The evaluation of the obtained sample was also in accordance with Example 1.

The initial characteristics of the obtained sample are 6.2% ±
0.7%, shunt resistance is 12 KΩcm ² ± 1 KΩcm
² , which was a good characteristic.

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

The solar cell characteristics of the sample after the temperature / humidity cycle test were measured, and the rate of decrease was 3% of the initial value, and significant deterioration was hardly caused. When the shunt resistance was measured, it was 11% lower than the initial value. From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Example 27 Acrylic cationic electrodeposition resin (Acrylic Clear A-7X manufactured by Uemura Kogyo Co., Ltd. minimum film forming temperature of about 60 ° C.) was used as an acrylic cationic electrodeposition resin (minimum film forming temperature of about 25 ° C.). The same procedure as in Example 24 was performed except that the temperature was changed to ° C). The evaluation of the obtained sample was in accordance with Example 1.

The initial characteristics of the obtained sample are 6.0% ±
1.4%, shunt resistance is 20 KΩcm ² ± 5 KΩcm
² , which was a good characteristic. However, with this paint, initial characteristics were significantly reduced to 4.0% unless it was washed with water immediately after the completion of electrodeposition.

Next, the reliability test of the sample obtained by sufficiently washing with water was conducted in the same manner as in Example 1. When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, it was 9% lower than the initial value. From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Example 28 Acrylic cationic electrodeposition resin (Acrylic Clear A-7X manufactured by Uemura Kogyo Co., Ltd.) was changed to an epoxy cationic electrodeposition resin (solid content 10% manufactured by Uemura Kogyo Co., Ltd.). Other than that was produced similarly to Example 24. The evaluation of the obtained sample was in accordance with Example 1.

The initial characteristics of the obtained sample are 6.0% ±
0.7%, shunt resistance is 25 KΩcm ² ± 3 KΩcm
² , which was a good characteristic.

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, it was 9% lower than the initial value. From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 29) Implementation was carried out except that the cationic cation electrodeposition resin of acrylic resin (Acrylic Clear A-7X manufactured by Uemura Industry Co., Ltd.) was changed to the cationic electrodeposition resin resin of fluorine (Uemura Industry Co., Ltd.). Prepared as in Example 24. The evaluation of the obtained sample was in accordance with Example 1.

The initial characteristics of the obtained sample are 6.7% ±
0.7%, shunt resistance is 20KΩcm ² ± 2KΩcm
² , which was a good characteristic.

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, it was 7% lower than the initial value. From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 30) A cationic cationic electrodeposition resin (acrylic clear A-7X manufactured by Uemura Kogyo Co., Ltd.) was modified with a cationized oligomer (polyethylene glycol having a molecular weight of 2200 and modified at both terminals with carboxylic acid (Kawaken Fine Co., Ltd.). ) And a cationic epoxy (a reaction product of Nagase Kasei Co., Ltd. Weisste)) was used, and the same procedure as in Example 24 was performed. The evaluation of the obtained sample was in accordance with Example 1.

The initial characteristics of the obtained sample are 5.5% ±
1.1%, shunt resistance is 7 KΩcm ²± 1 KΩcm²
It was a good characteristic.

Next, a reliability test of this sample was conducted in the same manner as in Example 1.

[0232] When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the rate of decrease was 7% of the initial value, and no significant deterioration occurred. When the shunt resistance was measured, it was 26% lower than the initial value. From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Example 31 An acrylic cationic electrodeposition resin (acrylic clear A-7X manufactured by Uemura Kogyo Co., Ltd.) was used as an epoxy / polybutadiene cationic electrodeposition resin (RADICOAT N800 black pigment manufactured by Nippon Pain Co., Ltd.). Production was carried out in the same manner as in Example 24, except that the inside was changed to the above. The evaluation of the obtained sample was in accordance with Example 1.

The initial characteristics of the obtained sample are 5.7% ±
0.8%, shunt resistance is 20KΩcm ² ± 3KΩcm
² , which was a good characteristic.

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, the rate of decrease was 1% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, it was 7% lower than the initial value. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Embodiment 32) The energization time during electrodeposition of 7 seconds is set to 3
It was produced in the same manner as in Example 24 except that the time was changed to seconds.

Ten samples were manufactured by the above manufacturing method. It was confirmed by a scanning electron microscope that the area was about 0.7 times larger than that of the shunt area. The initial characteristics of the obtained sample were a conversion efficiency of 5.4% ± 0.9% and a shunt resistance of 10 KΩcm ² ± 1 KΩcm ² .

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

The solar cell characteristics of the sample after the temperature / humidity cycle test were measured. As a result, the rate of decrease was 3% of the initial value, and significant deterioration did not occur. Further, the shunt resistance was measured and found to be 17% lower. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 33) A solar cell having the structure shown in Fig. 5 was produced in substantially the same manner as in Example 24.

First, a transparent upper electrode 106 of SnO ₂ was deposited on a Corning 7059 substrate 101 of 30 cm square by using a vapor deposition device (not shown). Then, the upper electrode 106
Was etched and patterned so that subcells each having a width of 2 cm were arranged side by side with a gap having a width of 5 mm. next,
A p-layer 105, an i-layer 104, and an n-layer 103 were deposited so as to substantially overlap with the upper electrode 106 using a metal mask. The electrodeposition method was in accordance with Example 24. Next, the substrate 101
Was charged into a sputtering device (not shown) using a metal mask to form an aluminum lower electrode 102, and a single cell of 10 cm in series and 30 cm square was produced. Ten samples were manufactured by the above manufacturing method.

The initial characteristic of the obtained sample was that the conversion efficiency was 6.
2% ± 0.8%, shunt resistance is 22KΩcm ² ± 3K
Was Ωcm ² .

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after the completion of the temperature and humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. In addition, the shunt resistance was measured and found to be 1% lower than the initial value. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

(Example 34) A polycrystalline solar cell having the structure shown in Fig. 7 was manufactured in substantially the same manner as in Example 24.

As in Example 24, the lower electrode 102 was formed on the SUS430BA substrate (30 cm × 30 cm, thickness 0.2 mm) 101. The substrate 101 is taken out and put in an RF plasma CVD film forming apparatus (not shown),
The i layer 104 and the p layer 105 were deposited in this order. afterwards,
After the substrate 101 was taken out of the oven and cooled, electrodeposition was performed in the same manner as in Example 24. Then, as in Example 24,
Transparent upper electrode 10 having a function also as an antireflection effect
6 was deposited at 700 Å. Further, a bus bar 108 of copper foil with an adhesive was laminated to form a single cell of 30 cm square. Similarly, ten samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 6.4% ±
0.8%, shunt resistance is 8 KΩcm ²± 1 KΩcm²
It was a good characteristic. Next, the reliability test of this sample
Was carried out in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, the rate of decrease was 4% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, the decrease was 15%. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 35) The following solar cell was prepared in substantially the same manner as in Example 24 except that the triple solar cell shown in Fig. 4 was used as the solar cell. First, a lower electrode 102 composed of a textured AlSi layer and a ZnO layer as a high resistance transparent conductive member for shunt prevention is formed on a substrate 101, and then placed in a microwave plasma CVD film forming apparatus (not shown), An n layer 103, an i layer 104, and a p layer 105 were deposited in this order to form a bottom layer. At this time, the i layer 104 was a-SiGe. Next, the n-layer 113,
The i layer 114 and the p layer 115 were deposited in this order to form a middle layer. The i layer 114 was made of a-SiGe similarly to the bottom layer. Next, the n layer 123, the i layer 124, and the p layer 125 were deposited in this order to form a top layer. The i layer 124 is a-
SiGe. Next, the acrylic cationic electrodeposition coating used in Example 1 was used for electrodeposition treatment. Then, it was washed and cured. Next, the transparent upper electrode 106 having a function of also having an antireflection effect as in Example 1 is set to 700 Å
Deposited. In ₂ O ₃ (IO) was used as the upper electrode. The grid electrode 107 is printed, and the bus bar 10 is further printed.
8 was laminated to produce a 30 cm square triple cell. Similarly, ten samples were prepared. Further, encapsulation of these samples was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 7.7% ±
0.7%, shunt resistance is 29 KΩcm ² ± 3 KΩcm
² , which was a good characteristic. Next, the reliability test of this sample was performed in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, the rate of decrease was 2% of the initial value, and significant deterioration did not occur. When the shunt resistance was measured, the decrease was 8%. From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.
(Example 36) A solar cell having the layer structure shown in Fig. 3 was produced as follows. First, in the same manner as in Example 24,
The p-type layer 105 was formed on the SUS substrate.

Next, the back surface of the substrate 101 was covered with an insulating film made of plastic, and the back surface of the substrate 101 was immersed in the electrolytic bath 301 of FIG. 9 so that the back surface of the substrate 101 was not electrodeposited. As the counter electrode 303, a SUS304 stainless plate having a size of 30 cm × 30 cm so that the polar ratio was 1: 1 and the back side of which was sealed with an insulating film made of plastic was used. The electrodeposition coating material 302 is an acrylic-melamine-based anion electrodeposition coating material having a solid content of 10%, and has an electric conductivity of 620 μS / cm.
The pH was 8.47. Bath temperature during electrodeposition is 25.4 ° C
Then, a voltage of plus 10 V was applied to the substrate 101, the electrodeposition end time was set to 10 seconds, the distance between the electrodes was fixed to 50 mm, and electrodeposition was performed. The relationship between the current flowing at this time and the time was as shown in FIG. After electrodeposition, the solar cell 100 is quickly pulled up from the electrodeposition tank, thoroughly washed with pure water, unreacted electrodeposition paint is washed off, and placed in an oven at 50 ° C.
It was left for 10 minutes to dry the water. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 20 minutes to cure the electrodeposition resin. After that, the substrate 101 was taken out of the oven, and after cooling, a part of the substrate 101 was cut out and observed with a scanning electron microscope. As a result, hemispherical deposits having a diameter of about 5 μm to 50 μm were scattered on the surface of the semiconductor layer 105. Was observed. When the infrared absorption of this portion was analyzed by using FTIR with a microscopic function, it was confirmed that the carbonyl group of the acrylic ester was absorbed and the electrodeposition paint was deposited. OB of this sample
When the IC image was observed, it was confirmed that only the deposited portion of the electrodeposition paint did not generate power, and thus the deposited film was deposited only on the shunt portion.

Then, similarly to the above-mentioned method, only the electrodeposition time is 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, 70 seconds.
Samples were prepared by changing the time in seconds, 80 seconds, 90 seconds, and 100 seconds. After the thermosetting treatment, the film was placed in a resistance heating vapor deposition device (not shown), and while maintaining the internal pressure of 1 × 10 ⁻⁴ Torr while introducing oxygen, an alloy of In and Sn was vapor-deposited by resistance heating to also serve as an antireflection effect. Transparent ITO upper electrode 1 with function
06 was deposited to 700 liters.

Then, in the same manner as in Example 1, grid electrodes and bus bars were formed to produce a 30 cm square single cell. Subsequently, encapsulation of these samples was performed.

When these initial characteristics were measured, Table 1
The result is similar to. That is, it was found that the electrodeposition can be controlled by time, and that the electrodeposition time is preferably 30 to 90 seconds for an applied voltage of 10V.

After that, as in the method described above, 10V6
After electrodeposition under the condition of 0 seconds, 10 samples were prepared by performing encapsulation by the above method.

A reliability test of the obtained sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after the end of the test were measured using a simulator in the same manner as in the initial stage, the average conversion efficiency was 5% lower than the initial conversion efficiency, and no significant deterioration occurred. Also, when the shunt resistance is measured, it is about 10%.
There was no significant deterioration in It has been found that electrodeposition has good results.

From the results of this example, it was found that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention had good yield, good characteristics, and high reliability.

Example 37 Next, a solar cell having the structure shown in FIG. 5 was produced in substantially the same manner as in Example 36.

First, a transparent upper electrode 106 of SnO ₂ was deposited on a Corning 7059 substrate 101 of 30 cm square by using a vapor deposition device (not shown). Then, the upper electrode 106
Was etched and patterned so that subcells each having a width of 2 cm were arranged side by side with a gap having a width of 5 mm. next,
A p-layer 105, an i-layer 104, and an n-layer 103 were deposited so as to substantially overlap with the upper electrode 106 using a metal mask. Next, the substrate 101 was dipped in the electrodeposition bath 201 and electrodeposited using an acrylic-melamine-based anion-based electrodeposition coating material.
As the counter electrode 203, a pole ratio of 30 is set to 30.
A SUS304 stainless steel plate having a size of cm × 30 cm, the back side of which was sealed with a plastic insulating film with respect to the substrate 101, was used. Electrodeposition paint 302
Is an acrylic-melamine-based anionic electrodeposition coating composition having a solid content of 8.0%, and its electrical conductivity and pH were measured by the same method as in Example 36. The results were 720 μS / cm and 8.2, respectively.
It was 7. A voltage of plus 10 V was applied to the substrate 101 for 30 seconds under a bath temperature of 25.3 ° C., and electrodeposition was performed with the distance between the electrodes being 50 mm. At this time, as the voltage application method, as shown in FIG. 17, the voltage was increased at a rate of 1 V / second from the start of application by a soft start method so that the voltage was 10 V in 10 seconds. The relationship between current and time at this time is shown in FIG.
It became 8. As a result, when a voltage is applied between the electrodes,
It is possible to prevent a rapid electric current from flowing in the initial stage, and to obtain a uniform resin deposition. After electrodeposition, the solar cell 100 was quickly pulled out from the electrodeposition tank, thoroughly washed with pure water, and the unreacted electrodeposition paint was washed off. This was placed in an oven at 50 ° C. and left for 20 minutes to dry the water. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 30 minutes to cure the electrodeposition resin. Further, the substrate 101 is put into a sputtering device (not shown) using a metal mask to form an aluminum lower electrode 102,
A single cell of 10 cm in series and 30 cm square was produced. Ten samples were manufactured by the above manufacturing method.

The initial characteristic of the obtained sample was that the conversion efficiency was 6.
The shunt resistance was 9 ± 1% and 40 to 65 KΩcm ² .

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

When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the deterioration rate was 4% with respect to the initial value and no deterioration occurred. In addition, when the shunt resistance was measured, there was almost no change.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the method of manufacturing a solar cell of the present invention has good characteristics and good durability.

(Example 38) A solar cell having the structure shown in Fig. 3 was manufactured in substantially the same manner as in Example 36 except that the kind of electrodeposition coating material and the applied voltage were changed.

As in Example 36, the lower electrode 102 was formed on the SUS430BA substrate (30 cm × 30 cm, thickness 0.2 mm) 101. The substrate 101 is taken out and placed in an RF plasma CVD film forming apparatus (not shown) to form the n layer 103, i.
The layer 104 and the p layer 105 were deposited in this order.

Next, as in Example 36, the substrate 101 was used.
The back side of was covered with an insulating film made of plastic, and immersed in the electrodeposition tank 301 of FIG. The electrodeposition coating material 302 was an acrylic-melamine-based anion electrodeposition coating material having a solid content of 10.5% and containing a large amount of styrene in order to strengthen the cross-linking, and the electric conductivity was measured to be 518 μS / cm.
The pH was 8.05. Under the bath temperature of 24.8 ° C., the voltage applied to the substrate 101 was kept at 2 V for 30 seconds, and the electrode distance was set to 50 mm for electrodeposition. After electrodeposition, solar cell 10
0 was quickly pulled up from the electrodeposition tank, thoroughly washed with pure water, the unreacted electrodeposition paint was washed away, 50 ° C. was placed in an oven, and the water was dried by leaving it for 20 minutes. afterwards,
Raise the oven temperature at a rate of 10 ° C / min to 150 ° C
The temperature was maintained for 30 minutes to cure the electrodeposition resin. Examples 36 and 37 by increasing the content of styrene
It was possible to lower the curing temperature by about 30 ° C. After that, the substrate 101 was taken out from the oven, cooled, and then, similarly to Example 36, 700Å of a transparent upper electrode 106 having a function also as an antireflection effect was deposited. Next, Example 1
The grid 107 was printed in the same manner as above. Further, a bus bar 108 of copper foil with an adhesive was laminated to form a single cell of 30 cm square.

Further, the voltage at the time of electrodeposition was changed to 5V, 7V, 10V, 15V, 20V, 30V by the same procedure as above to prepare samples.

When the initial characteristics of the obtained sample were measured by the same method as described above, the result showed the same tendency as shown in FIG. 14, and it was found that the voltage during electrodeposition is preferably 5V to 20V.

Therefore, the applied voltage was electrodeposited at 15 V, the grid electrode 107 was printed by the same method as described above, and the bus bar 1
Ten samples were prepared by adhering 08. Further, encapsulation of this sample was performed in the same manner as in Example 1.

Next, the ten samples were evaluated for durability characteristics in the same manner as in Example 1. When the solar cell characteristics of the sample after the temperature / humidity cycle test were measured, the average value was 3.2% lower than the initial value, and no deterioration occurred. When the shunt resistance was measured, there was almost no significant deterioration with a decrease of about 8%, good characteristics were obtained, and durability was also good. Further, by containing a large amount of a non-functional monomer such as styrene in the electrodeposition resin used, a strong electrodeposition resin was laminated and the durability could be increased.

(Example 39) A solar cell having the structure shown in Fig. 3 was manufactured in substantially the same manner as in Example 36 by changing the electrodeposition paint and using the constant current method.

First, in the same manner as in Example 39, SUS430B
A substrate (30 cm x 30 cm, thickness 0.2 mm) 10
1. A lower electrode 102 is formed on the first electrode 1 and then an RF not shown
The n layer 103 and the i layer 10 were placed in a plasma CVD film forming apparatus.
4, the p layer 105 was deposited in this order.

Next, the back side of the substrate 101 was covered with an insulating film made of plastic and immersed in the electrodeposition bath 301 shown in FIG. An electrodeposition coating material 202 having a solid content of 10.5%, in which polyfluorinated ethylene fine particles were dispersed in an acrylic anion electrodeposition coating material, was used, where the electrical conductivity was 560 μS / cm and the pH was 7.93. At a bath temperature of 24.4 ° C,
It was subjected to electrodeposition treatment. A constant current method is used for electrodeposition, and the current is set to 0.
2 A / dm ² , 0.5 A / dm ² , 1.0 A / dm ² ,
The current was set to 1.5 A / dm ² and 2.0 A / dm ² , and each was energized for 10 seconds. In the constant current method, the voltage tended to increase as the electrodeposition resin was laminated. Since the voltage gradually rises with electrodeposition, it is necessary to manage the voltage so that it is below the breakdown voltage of the solar cell. After washing thoroughly with pure water to wash off the unreacted electrodeposition paint, 50 ° C
It was placed in the oven and dried for moisture for 10 minutes. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 20 minutes to cure the electrodeposition resin. After that, the substrate 101 was taken out from the oven, cooled, and then, similarly to Example 36, 700Å of a transparent upper electrode 106 having a function also as an antireflection effect was deposited.
Then, the grid 107 was printed in the same manner as in Example 36. Next, the copper foil bus bar 108 with an adhesive is laminated,
A 30 cm square single cell was prepared.

Table 3 shows the results of the measurement of the initial characteristics by the method described above. From Table 3, the current during electrodeposition is 0.5 A / dm ²
Therefore, it was found that 1.5 A / dm ² is preferable.

Thereafter, 10 samples were prepared under the conditions of electrodeposition current of 1.0 A / dm ² in the same manner as above. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristic of the obtained sample is that the conversion efficiency is 6.4.
% ± 0.6%, which was a good characteristic.

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

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, it was found to be 2% lower than the initial value, and no deterioration occurred. When the shunt resistance was measured, there was almost no change.

[0282] Further, the samples were further subjected to a weather resistance test for 1000 hours using a sunshine weather meter, and the solar cell characteristics of these samples were measured after the test was completed. It turns out that it can withstand the use of. Further, it was possible to improve water resistance and weather resistance by dispersing a fluorine-based or silicon-based filler having a small water absorption amount and high water repellency in the paint.

(Example 40) A solar cell was prepared as follows by substantially the same method as in Example 36 except that the structure of the solar cell was the triple type solar cell shown in Fig. 4. First, a lower electrode 102 in which a light reflection layer of AlSi having a texture structure and a light reflection enhancement layer of a high resistance transparent conductive member ZnO for shunt prevention were laminated was formed on a substrate 101. Then, the substrate was placed in a microwave plasma CVD film forming apparatus (not shown), and the n layer 103, the i layer 104, and the p layer 105 were laminated in this order to form a bottom layer. At this time, the i layer 104 is aS
iGe. Next, the n layer 113, the i layer 114, and the p layer 1
The layers were laminated in the order of 15 to form a middle layer. i layer 114
Was a-SiGe as in the bottom layer. Next, n layer 1
The top layer was formed by stacking 23, the i layer 124, and the p layer 125 in this order. The i layer 124 was a-Si.

Next, an acrylic-melamine-based anion electrodeposition coating material 202 was used, the distance between the electrodes was 50 mm, and the applied voltage was 10 mm.
The electrodeposition treatment was performed under the conditions of V and electrodeposition time of 30 seconds. Then, it wash | cleaned and heat-hardened. Then, as in Example 36, 700 Å of transparent upper electrode 106 having a function of also having an antireflection effect was laminated. I as the upper electrode 106
n ₂ O ₂ (IO) was used. The grid electrode 107 is printed, and the bus bar 108 is further laminated, and 30c shown in FIG.
An m-square triple cell was prepared. Similarly, ten samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 7.5% ±
0.6% and the shunt resistance is 60 KΩcm ^{2 to} 95 K
It was Ωcm ² and had good characteristics and little variation.

Next, the reliability test of this sample was conducted in the same manner as in the example.

When the solar cell characteristics of the sample after the completion of the temperature / humidity cycle test were measured, the conversion efficiency was 4.5% lower than the initial value, and no significant deterioration was observed.
Regarding the shunt resistance, there was almost no significant deterioration with a decrease of about 5%, and there was almost no change.

From this example, it is understood that the solar cell manufactured by the solar cell manufacturing method of the present invention has a good yield, good characteristics, and good durability.

Example 41 A solar cell having the layer structure shown in FIG. 3 was produced as follows. First, in the same manner as in Example 1, Cr, a semiconductor layer, and ITO were deposited on the SUS substrate.

Next, the back side of the substrate 101 was covered with an insulating film made of plastic, and immersed in the electrolytic cell 201 of FIG. 9 so that no current would flow to the back side of the substrate 101 during passivation. As the counter electrode 303, a SUS304 stainless steel plate having a size of 30 cm × 30 cm with a polar ratio of 1: 1 and a back side of the substrate 101 sealed with a plastic insulating film was used. 10% of AlCl ₃ as passivation liquid
The solution was used. The conductivity of this solution is 600 mS / cm
Met. Next, with the substrate 101 side as a minus, 1.5
A voltage was applied at V for 3 seconds to perform passivation. Then, the solar cell 100 was pulled up from the electrolytic layer 301, thoroughly washed with pure water, rinsed away with the passivation liquid, placed in an oven at 80 ° C., and allowed to stand for 30 minutes to dry the water. Next, the substrate 101 was placed in a screen printer (not shown), and grid electrodes 107 having a width of 100 μm and a length of 8 cm were printed at intervals of 1 cm. At this time, the conductive paste is 70 parts of Ag filler and 3 parts of polyester binder.
A composition containing 0 part (volume ratio) and 20 parts of ethyl acetate as a solvent was used. After printing, the substrate 101 was put in an oven and kept at 150 ° C. for 30 minutes to cure the conductive paste.

Further, a bus bar 108 of copper foil with an adhesive having a width of 5 mm was adhered as shown in FIG. 8 to prepare a 30 cm square single cell.

Next, the voltages at the time of passivation were 2.0V, 2.5V, 3.0V, 3.5V, 4.0 in the above procedure.
Samples were prepared by changing the voltages to V, 4.5V, 5,0V, 5.5V and 6.0V. For comparison, a sample without passivation was prepared under the same conditions as in Comparative Example 1. The results of measuring the initial characteristics of the above samples are shown in FIG.

The conversion efficiency of FIG. 19 is shown by standardizing the conversion efficiency of the sample of Comparative Example 1. It can be seen from FIG. 19 that when the voltage is about 4 V, the shunt resistance increases and the solar cell characteristics are good. The reason why the conversion efficiency decreases when the voltage is 4.5 V or higher is that the upper electrode 106 in the normal portion also has a high resistance due to excessive passivation, which increases the series resistance.

Next, ten passivated substrates 101 were prepared by the above method under the condition of 4V for 3 seconds, and electrodeposition was performed as follows using the electrolytic cell 301 in FIG.
First, the back surface of the substrate 304 was masked in the same manner as described above, and a sealed SUS304 stainless steel plate was used as the counter electrode 203 in the same manner as described above. The size was 30 cm × 30 cm so that the polar ratio was 1: 1. As the electrodeposition coating 302, an epoxy-based cationic electrodeposition coating having a solid content of 10% was used, and melamine was used for crosslinking. The conductivity of this liquid was 600 μS / cm, and the weight average molecular weight was 8,000. The liquid temperature was kept at 25 ° C. during electrodeposition. The substrate 304 and the counter electrode 203 were immersed in the electrodeposition bath 301, and the substrate 304 and the counter electrode 303 were held for 30 seconds in order to adapt to the liquid. After that, a voltage of minus 2 V was applied to the substrate 304 and held for 10 seconds for electrodeposition. In addition, the amount of Coulomb of the flowing current was 50 mC. The solar cell 100 is pulled up from the electrodeposition tank 301, thoroughly washed with pure water, and the unreacted electrodeposition paint is washed off.
It was put in an oven at 0 ° C. and left for 30 minutes to dry the water. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 30 minutes to cure the electrodeposition resin.

Further, in the same manner as the above-mentioned method, a sample was prepared by changing only the voltage during electrodeposition from 0V to 60V. Next, a grid electrode and a bus bar were formed on the substrate 101 by the method described above, and a 30 cm square single cell was produced. The conversion efficiency of the obtained sample was measured by the same method as described above. FIG. 20 shows the relationship between the electrodeposition voltage and the conversion efficiency. In the figure, the electrodeposition voltage of 0 V is set to 1 and standardized. From the figure, it was found that a suitable voltage during electrodeposition is 10V to 30V. In addition, the conversion efficiency of the voltage of 30 V or more is low, because the voltage is applied so as to be forward biased to the solar cell during electrodeposition, and the electrodeposition film is deposited on the normal portion other than the defective portion. This is because the electrodeposited film increases the contact resistance of the grid electrode.

Next, a part of the sample having an electrodeposition voltage of 10 V with good conversion efficiency was cut out and observed with a scanning electron microscope. As a result, hemispherical deposition with a diameter of about 5 μm to 50 μm was formed on the surface of the upper electrode 106. Objects were scattered and observed. When the infrared absorption of this portion was analyzed by using FTIR with a microscope function, it was confirmed that there was absorption of a carbonyl group and the electrodeposition coating was deposited. Further, when the OBIC image of this sample was observed, it was confirmed that only the deposited portion of the electrodeposition coating did not generate power, and thus the deposited portion was deposited only on the shunt portion. The area where the electrodeposition paint was deposited was 10 times or less the area of the shunt portion.

Next, passivation was performed under the condition of 4V for 3 seconds in the same manner as the above-mentioned method, and electrodeposition was performed at a voltage of 10V. After that, the grid electrode 107 and the bus bar 108 were adhered by the method described above to prepare 10 single cells of 30 cm square.

The initial characteristics and the characteristics after the reliability test of the obtained sample were measured by the above-mentioned methods, and the shunt resistance was also measured. The results are shown in FIGS. 21 and 22. The results in the figure have the same structure and are standardized by a sample (Comparative Example 1) produced without passivation and electrodeposition.

From the above results, in the comparative example, the variation in the initial characteristics was large and the deterioration after the reliability test was large, whereas the solar cell of this example showed excellent characteristics.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the method of manufacturing a solar cell of the present invention has good yield, good characteristics, and good durability.

Example 42 A thin film polycrystalline solar cell having a pn junction was prepared.

Corning 7059 substrate (30 cm × 30
The lower electrode 102 was formed on the (cm, thickness 3.0 mm) 101. The substrate 101 was taken out and placed in an RF plasma CVD film forming apparatus (not shown) to deposit the n layer 103 and the p layer 105 in this order.

Next, the upper electrode 106 was formed, and the substrate 101 was immersed in the electrodeposition bath 301 shown in FIG. In this example, passivation and electrodeposition were performed under the following conditions. ──────────────────────────────────── Process process Electrolysis solution condition ──────── ───────────────────────────── Passivation AlCl ₃ (10% aqueous solution) 4V × 3 seconds 60mS / cm Electrodeposition Epoxy-based cation electrode Coating material 10V × 20 seconds (including fluoropolymer filler) Conductivity: 600 μS / cm (1V / second) Weight average molecular weight: 8000 Liquid temperature: 25 ° C. Coulomb amount: 50 mC Solid content: 18% ───────── ──────────────────────────── The voltage is applied during electrodeposition from 0V to 10V at 1V.
Swept at / sec and held for 20 seconds thereafter. After the electrodeposition was completed, the electrodeposition resin was thoroughly washed with pure water and the electrodeposition resin was cured in an oven. After that, the substrate 101 was taken out from the oven and cooled, and then the grid electrode 107 was formed and the bus bar 108 of copper foil with adhesive was laminated in the same manner as in Example 41.
A cm square single cell was produced. Similarly, 10 sheets of samples were prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

For comparison, a sample (Comparative Example 42) was prepared in the same manner as above except that electrodeposition was not performed.

The initial characteristics and the average value and variation of the shunt resistance of the obtained sample are shown in FIGS. 23 and 24. Next, a reliability test was performed in the same manner as in Example 1, and the results of the solar cell characteristics and shunt resistance of the sample after the temperature and humidity cycle test are also shown in FIGS. 23 and 24.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 43) Using the apparatus shown in FIG.
The steps of passivation and electrodeposition were performed by a roll-to-roll method, and a solar cell having the layer structure shown in FIG. 11 was produced as follows.

Rolled in a thickness of 0.2 mm and a width of 3
SUS430BA substrate 501 with a length of 0 cm and a length of 100 m
While unrolling, a lower electrode 102, an n layer 103, an i layer 104, a p layer 105, and an upper electrode were formed in this order using a roll-to-roll film forming apparatus (not shown), and the film was wound again into a roll shape. Next, the roll-shaped substrate 501 was installed in the apparatus shown in FIG. 12 for continuously performing passivation and electrodeposition. The substrate 501 is delivered from the substrate delivery roller 502, and an electrolytic bath 504 for passivation, a cleaning bath 505, a drying furnace 506, an electrolytic bath 514 for electrodeposition, a cleaning layer 515,
After passing through the drying furnace 516, the take-up roller 503 is finally used.
Rolled up. At the same time, while the mask films 510 and 520 were being fed from the mass film feeding rollers 508 and 518, the back surface of the substrate 501 was wound around the mask and mask winding rollers 509 and 519. As the counter electrodes 511 and 521, a SUS304 stainless steel plate was used, the back side of which was sealed with a plastic insulating film with respect to the substrate 501 so that the polar ratio was 1: 1. The substrate was sent at a speed of 2 m / min. At this feed rate, the substrate 501 is the electrolytic cell 50 for passivation.
The lengths of the electrolytic baths 504 and 514 were designed so that the electrolytic baths 504 and 514 were soaked in No. 4 for 3 seconds and in the electrodeposition electrolytic bath 514 for 15 seconds. Passivation and electrodeposition were performed under the following conditions. ──────────────────────────────────── Process process Electrolysis solution condition ──────── ───────────────────────────── Passivation AlCl ₃ (5% aqueous solution) 4 V (continuous) 30 mS / cm Electrodeposition Epoxy cation electrode Coating material 15 V (continuous) Conductivity: 600 μS / cm Weight average molecular weight: 8000 Liquid temperature: 25 ° C. Solid content: 13% ──────────────────────── ───────────── After the passivation and electrodeposition steps were completed, the wound solar cell was cut into a length of 30 cm using a cutting machine. Next, in the same manner as in the method described in Example 1, the width 10
The grid electrodes 107 having a length of 0 μm and a length of 8 cm are spaced by 1 cm.
I printed it and cured it. Furthermore, a bus bar of copper foil with an adhesive having a width of 5 mm is adhered to form a single cell of 30 cm square.
0 sheets were produced. Encapsulation of these samples was performed as in Example 1. The initial characteristics and shunt resistance of the obtained sample were measured by the same method as in Example 41, and the results are shown in FIGS. 25 and 26. Further, the reliability test of these samples was performed in the same manner as in Example 1 to measure the conversion efficiency and the shunt resistance, which are also shown in FIGS. 25 and 26. The results of Comparative Example 1 are shown in the figure for comparison.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and high reliability.

(Example 44) Electrodeposition according to the constant current method was carried out to manufacture a solar cell having the layer structure shown in FIG. 3 in substantially the same manner as in Example 41. Similar to Example 41, the lower electrode 102, the n layer 103, the i layer 104, the p layer 105, and the upper electrode 106 were deposited on the substrate 101.

Next, as in the case of Example 41, the substrate 101 was used.
Was covered with a plastic insulating film, and was immersed in the passivation tank of FIG. 9 together with the counter electrode 301. Passivation and electrodeposition were performed under the following conditions. ──────────────────────────────────── Process process Electrolysis solution condition ──────── ───────────────────────────── Passivation AlCl ₃ (20% aqueous solution) 5V × 2 seconds 100mS / cm Electrodeposition Epoxy-based cation electrode Coating material ² mA / cm ² Conductivity: 600 μS / cm Weight average molecular weight: 8000 Liquid temperature: 25 ° C. Coulomb amount: 100 mC Solid content: 13% ─────────────────── ───────────────── Furthermore, in the same manner as described above, only the current during electrodeposition was 5 mA / cm ² , 10 mA / cm ² , 15 mA / c.
^{m 2, 20mA / cm 2,} 25mA / cm 2, 30mA
The amount of coulomb is 100 mC by changing to / cm ^2.
A sample was prepared as. These samples were processed in the same manner as in Example 1 to form a grid electrode 10 having a width of 100 μm and a length of 8 cm.
7 was printed at a distance of 1 cm and cured. Furthermore, width 5m
Adhere the copper foil bus bar 108 with an adhesive of m.
A cm square single cell was produced. The shunt resistance and the conversion efficiency of the obtained sample were measured by the same method as described above. The results are shown in Fig. 27. From FIG. 27, it was found that a suitable electric current during electrodeposition was 5 mA / cm ² to 20 mA / cm ² .

Next, in the same manner as the above-mentioned method, 15 mA / c
Electrodeposition was carried out under the condition of m ² to obtain a solar cell 100 with
A grid electrode 107 having a length of 8 μm and a length of 8 cm was printed at an interval of 1 cm, and a bus bar 108 of copper foil with an adhesive having a width of 5 mm was adhered to produce 10 single cells of 30 cm square.
Next, encapsulation of these samples was performed in the same manner as in Example 1. For comparison, a sample (Comparative Example 44) was prepared in the same manner as above except that electrodeposition was not performed.

The initial characteristics and the average value and variation of the shunt resistance of the obtained sample are shown in FIGS. 28 and 29. Next, a reliability test was performed in the same manner as in Example 1, and the solar cell characteristics and shunt resistance of the sample after the temperature and humidity cycle test were measured, and the results are also shown in FIGS. 28 and 29.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 45) Next, a triple solar cell 100 having the layer structure shown in Fig. 4 was produced in substantially the same manner as in Example 41. First, a lower electrode 102 composed of a textured AlSi layer and a ZnO layer as a high resistance transparent conductive material for shunt prevention is formed on a substrate 101, and then a microwave plasma CVD film forming apparatus (not shown) is formed. The bottom layer was formed by depositing the n-layer 103, the i-layer 104, and the p-layer 105 in this order. At this time, the i layer 104 is a-SiG
e. Next, the n layer 113, the i layer 114, and the p layer 115 were deposited in this order to form a middle layer. The i layer 114 was made of a-SiGe similarly to the bottom layer. Next, the n-layer 123, i
A layer 124 and a p layer 125 were deposited in this order to form a top layer. The i layer 124 was a-Si. Next, as in Example 4, 700 Å of transparent upper electrode 106 having a function of also serving as an antireflection effect was deposited. I as the upper electrode 106
n ₂ O ₃ (IO) was used.

Next, as in Example 1, the back side of the substrate 204 was covered with an insulating film made of plastic, and was immersed together with the counter electrode 303 in the electrodeposition bath of FIG. Passivation and electrodeposition were performed as follows. ──────────────────────────────────── Process process Electrolysis solution condition ──────── ───────────────────────────── Passivation AlCl ₃ (10% aqueous solution) 4V × 3 seconds 60mS / cm Electrodeposition Epoxy-based cation electrode Coating material 15V × 30 seconds Conductivity: 600μS / cm Weight average molecular weight: 8000 Liquid temperature: 25 ° C Coulomb amount: 50mC Solid content: 18% ──────────────────── ───────────────── These samples were processed in the same manner as in Example 1 to obtain a width of 100 μm,
A grid electrode 107 having a length of 8 cm was printed and cured at an interval of 1 cm. Further, a bus bar 108 of copper foil with adhesive having a width of 5 mm was adhered to produce a 30 cm square triple cell. Next, encapsulation of these samples was performed in the same manner as in Example 1. For comparison, a sample (Comparative Example 45) was prepared in the same manner as in Example 45 except that electrodeposition was not performed.
Was produced.

The initial characteristics of the obtained sample were measured in the same manner as in Example 1 to obtain the conversion efficiency and the shunt resistance.
0, shown in FIG. The reliability test of these samples was performed, and the solar cell characteristics and shunt resistance after the test were measured, and the results are also shown in FIGS. 30 and 31.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and high reliability.

Example 46 A solar cell having the layer structure shown in FIG. 3 was prepared as follows. First, the lower electrode, the semiconductor layer, and the upper electrode were formed on the SUS substrate in the same manner as in Example 1.

Next, the back side of the substrate 101 was covered with an insulating film made of plastic, and immersed in the electrolytic cell 301 of FIG. 9 so that no current would flow to the back side of the substrate 101 during passivation. As the counter electrode 303, a SUS304 stainless plate having a size of 30 cm × 30 cm so that the polar ratio was 1: 1 and the back side of which was sealed with an insulating film made of plastic was used. As the passivation liquid, 1 of AlCl ₃ is used.
A 0% solution was used. The conductivity of this solution is 60 mS / c
It was m. Next, with the substrate 101 side as a minus, 4V
Then, the voltage was applied for 3 seconds to perform passivation. Then, the solar cell 100 was pulled up from the electrolytic cell 301, thoroughly washed with pure water, the passivation liquid was washed off, placed in an oven at 80 ° C., and allowed to stand for 30 minutes to dry the water.

Electrodeposition was carried out as follows using the electrolytic cell 301 of FIG. First, the back surface of the substrate 304 was masked in the same manner as described above, and a sealed SUS304 stainless plate was used as the counter electrode 303 in the same manner as described above. 30c so that the pole ratio is 1: 1
The size was m × 30 cm. As the electrodeposition paint 302, an acrylic anion electrodeposition paint having a solid content of 10% was used, and melamine was used for crosslinking. The conductivity of this solution is 800 μS /
cm and the weight average molecular weight was 5000. The liquid temperature was kept at 25 ° C. during electrodeposition. Substrate 304 and counter electrode 20
3 was immersed in the electrolytic bath 301, and the substrate 101 and the counter electrode 303 were held for 30 seconds in order to adapt to the liquid. After that, a voltage of plus 2 V was applied to the substrate 304 and kept for 10 seconds for electrodeposition. The relationship between the current flowing at this time and the time was as shown in FIG. In addition, the amount of Coulomb of the flowing current was 50 mC.

The solar cell 100 was pulled up from the electrolytic cell 201, thoroughly washed with pure water, the unreacted electrodeposition paint was washed off, placed in an oven at 50 ° C., and left for 30 minutes to dry the water. Then, the temperature of the oven was raised at a rate of 10 ° C./minute, and after reaching 180 ° C., the temperature was kept for 30 minutes to cure the electrodeposition resin. Further, similarly to the method described above, only the voltage during electrodeposition was changed from 0V to 60V to prepare a sample. Next, the bus bar of the grid electrode 107 was adhered by the method described above to produce a single cell of 30 cm square.

The shunt resistance and conversion efficiency of the obtained sample were measured by the same method as described above. The results are shown in Fig. 33. From FIG. 33, it was found that a suitable voltage during electrodeposition is 10V to 20V. Further, it is considered that the conversion efficiency decreases at a voltage of 50 V or higher because the solar cell breaks down because a reverse bias is applied to the solar cell during electrodeposition. Next, an electrodeposition voltage of 10 V with good conversion efficiency
When a part of the sample was cut out and observed with a scanning electron microscope, the surface of the upper electrode 106 was about 5 μm to 50 μm.
Hemispherical deposits with a diameter of 1 were observed. The infrared absorption of this portion was analyzed by using FTIR with a microscopic function, and it was confirmed that there was absorption of a carbonyl group and the electrodeposition coating was deposited. Further, when the OBIC image of this sample was observed, it was confirmed that only the deposited portion of the electrodeposition coating did not generate power, and therefore the deposited film was deposited only on the shunt portion. The area where the electrodeposition paint was deposited was 10 times or less the area of the shunt portion.

Then, passivation was performed under the condition of 4V for 3 seconds in the same manner as in the above-mentioned method, and electrodeposition was performed at a voltage of 10V. Then, the grid electrode 1 is formed in the same manner as described above.
The bus bar 108 of 07 was formed, and 10 single cells of 30 cm square were prepared. Next, encapsulation of these samples was performed.

The initial characteristics of the obtained sample were measured by the method described above.
It was measured and the conversion efficiency was calculated to be 6.5% ± 0.5%.
Yes, and shunt resistance is 35 KΩcm²~ 90 KΩ
cm ²The characteristics were good and there was little variation.

A reliability test was performed on these samples. Next, the solar cell characteristics of the sample after the test were measured using a simulator in the same manner as in the initial stage. The conversion efficiency after the test was 2% lower than the initial conversion efficiency, and no significant deterioration occurred. It was Further, when the shunt resistance was measured, there was no significant deterioration with a decrease of about 10%.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

Example 47 A pn junction thin film polycrystalline solar cell was prepared.

Corning 7059 substrate (30 cm × 30
The lower electrode 102 was formed on the (cm, thickness 3.0 mm) 101. The substrate 101 was taken out and placed in an RF plasma CVD film forming apparatus (not shown) to deposit the n layer 103 and the p layer 105 in this order. The n layer is a thin film polycrystal. next,
The upper electrode 106 was formed, and passivation was performed at 4 V for 3 seconds in the same manner as in Example 46. Furthermore, Example 4
Electrodeposition was performed in the same manner as in No. 6 as follows. First, the substrate 101 was immersed in the electrolytic bath 301 shown in FIG. In this example, the electrodeposition treatment was performed using the electrodeposition liquid 302 containing a fluorine-based anionic electrodeposition coating material containing a fluoropolymer filler.
After the electrodeposition was completed, the electrodeposition resin was thoroughly washed with pure water and the electrodeposition resin was cured in an oven. Then, the substrate 101 is taken out of the oven and cooled, and then the grid electrode 107 is cooled in the same manner as in the first embodiment.
To form a copper foil bus bar 108 with an adhesive,
A 30 cm square single cell was prepared. Similarly 10
A sample was prepared. Further, encapsulation of this sample was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample are 10.4% ±
The value was 1.5, which was a good characteristic with little variation. Also, the shunt resistance is 60 KΩcm ² to 125 KΩcm.
^{Was 2} .

Next, the reliability test of this sample was conducted in the same manner as in Example 1.

When the solar cell characteristics of the sample after completion of the temperature / humidity cycle test were measured, it was found to be 2% lower than the initial value, and no deterioration occurred. In addition, when the shunt resistance was measured, there was almost no change.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 48) Next, the steps of passivation and electrodeposition were performed by a roll-to-roll method, and a solar cell having a layer structure shown in FIG. 3 was produced as follows. Rolled in a thickness of 0.2 mm, width of 30 cm and length of 100
m of the SUS430BA substrate 301 while being unrolled, a lower electrode 10 is formed by using a roll-to-roll film forming apparatus (not shown).
Then, the n layer 103, the i layer 104, the p layer 105, and the upper electrode were formed in this order, and wound again in a roll shape. Next, the roll-shaped substrate was set in an apparatus for continuously performing passivation and electrodeposition shown in FIG. The substrate 501 is a substrate delivery roller 50.
Electrolyzer 50 for passivation from 2
4, cleaning tank 505, drying furnace 506, electrolytic tank 5 for electrodeposition
After passing through the cleaning tank 515, the cleaning tank 515, and the drying furnace 516, it was finally wound around the winding roller 503. At the same time, while masking the mask films 510 and 520 from the mask film feeding rollers 508 and 518, the back surface of the substrate 501 is masked and the mask winding rollers 509 and 51 are used.
I wound it up to 9. As the counter electrodes 511 and 521, the back side of the substrate 501 was sealed with a plastic insulating film so that the polar ratio was 1: 1 S
A US304 stainless plate was used. The substrate was sent at a speed of 2 m / min. At this feed rate, the substrate 501 is immersed in the passivation electrolytic bath 504 for 3 seconds and in the electrodeposition electrolytic bath 514 for 15 seconds.
A length of 04,514 was designed. Next, in the passivation electrolytic bath 504, a voltage of 4.0 V was applied with the substrate 501 side being positive, and in the electrodeposition electrolytic bath 514, the voltage was 15 V. As the electrodeposition coating, an acrylic anion electrodeposition coating having a solid content of 10% was used, and melamine was used for crosslinking. The electric conductivity of this liquid was 800 μS / cm, and the weight average molecular weight was 5,000. The liquid temperature was kept at 25 ° C. during electrodeposition.

After the passivation and electrodeposition were completed, the wound solar cell was cut into a length of 30 cm using a cutting machine. Then, in the same manner as in Example 46, the grid electrode 10 having a width of 100 μm and a length of 8 cm was used.
No. 7 was printed at intervals of 1 cm and cured. Furthermore, width 5mm
The bus bar of the copper foil with adhesive was adhered to prepare 10 single cells of 30 cm square. Next, encapsulation of these samples was performed in the same manner as in Example 1. The initial characteristics of the obtained sample were measured by the same method as in Example 1 and the conversion efficiency was determined to be 6.1% ± 0.5%, which was a good characteristic and had little variation. The shunt resistance was 1.5 KΩcm ² to 10 KΩcm ² .

The reliability test of these samples was performed in the same manner as in Example 1.

The conversion efficiency after the test was decreased by 2% on average with respect to the initial conversion efficiency, and no significant deterioration occurred. Further, when the shunt resistance was measured, there was no significant deterioration with a decrease of about 10%.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 49) Electrodeposition according to the constant current method was carried out to manufacture a solar cell having the layer structure shown in FIG. 3 in substantially the same manner as in Example 46. Similarly to Example 46, the lower electrode 102, the n layer 103, the i layer 104, the p layer 105, and the upper electrode 106 were deposited on the substrate 101.

Next, as in the 46th embodiment, the substrate 101 is used.
9 is covered with an insulating film made of plastic, and the passivation tank 301 of FIG.
Soaked in. Passivation was performed by applying a voltage of 4.0 V for 3 seconds with the substrate 304 as a plus. Next, as the electrodeposition paint 302, an acrylic anion electrodeposition paint having a solid content of 10% was used, and melamine was used for crosslinking. This liquid has an electric conductivity of 800 μS / cm and a weight average molecular weight of 5
It was 000. The liquid temperature was kept at 25 ° C. during electrodeposition. Board 3
04 and the counter electrode 303 are immersed in the electrolytic bath 301 so that the substrate 304 and the counter electrode 303 are soaked in liquid 3
Hold for 0 seconds. After that, apply a current of 2 m to the substrate 304.
It was set to A / cm ² and held for 10 seconds. The electric current that flowed was 100 mC / cm ² . Further, in the same manner as described above, only the electric current during electrodeposition was 5 mA / cm ² , 1
0 mA / cm ² , 15 mA / cm ² , 20 mA / c
A sample was prepared by changing the m ² and 30 mA / cm ² and setting the Coulomb amount to 100 mC. These samples were printed and cured in the same manner as in Example 1 by printing grid electrodes 107 having a width of 100 μm and a length of 8 cm at intervals of 1 cm.
Further, a bus bar 108 of copper foil with an adhesive having a width of 5 mm was adhered to produce a 30 cm square single cell. The shunt resistance and conversion efficiency of the obtained sample were measured in the same manner as the above-mentioned method, and the current during electrodeposition was 10 mA / cm ²
From this, it was found that 20 mA / cm ² is suitable.

Next, in the same manner as the above-mentioned method, 15 mA / c
Electrodeposition was carried out under the condition of m ² to obtain a solar cell 100 and a width of 100
A grid electrode 107 having a length of 8 μm and a length of 8 cm was printed at intervals of 1 cm, and a bus bar 108 of copper foil with an adhesive having a width of 5 mm was adhered to produce 10 single cells of 30 cm square. Next, encapsulation of these samples was performed.

The initial characteristics of the obtained sample were measured by the above-mentioned method, and the conversion efficiency was determined to be 6.7% ± 1.2%, which was a good characteristic with little variation. The shunt resistance was 10 KΩcm ² to 30 KΩcm ² .

The reliability test of these samples was performed in the same manner as in Example 1. Next, when the solar cell characteristics of the sample after the test were measured using a simulator as in the initial stage, the conversion efficiency after the test was 2% on average with respect to the initial conversion efficiency, and no significant deterioration occurred. Further, when the shunt resistance was measured, there was no significant deterioration with a decrease of about 10%.

From the results of this example, it is understood that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

(Example 50) Next, a triple solar cell 100 having a layer structure shown in Fig. 4 was produced in substantially the same manner as in Example 46. First, a lower electrode 102 consisting of a textured AlSi layer and a ZnO layer as a high resistance transparent conductive member for shunt prevention is formed on a substrate 101, and then placed in a microwave plasma CVD film forming apparatus (not shown). An n layer 103, an i layer 104, and a p layer 105 were deposited in this order to form a bottom layer. At this time, the i layer 104 is a-SiG
e. Next, the n layer 113, the i layer 114, and the p layer 115 were deposited in this order to form a middle layer. The i layer 114 was made of a-SiGe similarly to the bottom layer. Next, the n-layer 123, i
A layer 124 and a p layer 125 were deposited in this order to form a top layer. The i layer 124 was a-Si. Next, as in Example 46, 700 Å of transparent upper electrode 106 having a function of also serving as an antireflection effect was deposited. In ₂ O ₃ (IO) was used as the upper electrode 106.

Next, as in the 46th embodiment, the substrate 204 is used.
The back side of was covered with an insulating film made of plastic, and was immersed in the electrolytic cell 301 of FIG. 9 together with the counter electrode 303.
Passivation was performed by applying a voltage of 4.0 V for 3 seconds with the substrate 304 as a plus. Next, as the electrodeposition coating, an acrylic anion electrodeposition coating having a solid content of 10% was used, and melamine was used for crosslinking. The conductivity of this liquid is 800 μS
/ Cm and the weight average molecular weight was 5000. The liquid temperature was kept at 25 ° C. during electrodeposition. The substrate 304 and the counter electrode 303 were immersed in the electrolytic bath 301 and held for 30 seconds in order to adapt the substrate 304 and the counter electrode 303 to the liquid. After that, a voltage of 15V is applied to the substrate 304 and the voltage of 20V is applied.
Hold for a second. These samples were processed as in Example 1,
A grid electrode 107 having a width of 100 μm and a length of 8 cm was printed at a distance of 1 cm and cured. Further, a bus bar 108 of copper foil with adhesive having a width of 5 mm was adhered to produce a 30 cm square triple cell. Next, encapsulation of these samples was performed in the same manner as in Example 1.

The initial characteristics of the obtained sample were measured in the same manner as in Example 1 and the conversion efficiency was determined to be 7.2% ± 1.4%.
The characteristics were good and there were few variations. Also,
The shunt resistance was 35 KΩcm ² to 105 KΩcm ² .

The reliability test of these samples was performed, and the solar cell characteristics after the test were measured. The conversion efficiency after the test was decreased by 2% on average with respect to the initial conversion efficiency, and significant deterioration occurred. There wasn't. Further, when the shunt resistance was measured, there was no significant deterioration with a decrease of about 10%.

From the results of this example, it can be seen that the solar cell of the present invention manufactured by the solar cell manufacturing method of the present invention has good yield, good characteristics, and good durability.

[0350]

As described above, by constructing the solar cell according to the present invention, the defective portion can be selectively insulation-coated with the electrodeposition resin, and the shunt resistance can be 10 ³ Ωcm ² or more. Therefore, it is possible to provide an excellent large-area solar cell having high characteristics with a high yield.

Further, since the manufacturing method of the present invention does not require a special method and device for detecting defects and can adopt the roll-to-roll method, it has high mass productivity and is low in cost, and has a large area. A battery can be provided.

[0352]

[Table 1]

[0353]

[Table 2]

[0354]

[Table 3]

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a solar cell of the present invention in which a defective portion is insulation-coated.

FIG. 2 is a schematic view showing an example of a solar cell of the present invention in which a defective portion is insulation-coated.

FIG. 3 is a schematic diagram showing a structural example of a solar cell.

FIG. 4 is a schematic view showing a structural example of a solar cell.

FIG. 5 is a schematic view showing a structural example of a solar cell.

FIG. 6 is a schematic view showing a structural example of a solar cell.

FIG. 7 is a schematic diagram showing a structural example of a solar cell.

FIG. 8 is a schematic diagram showing a structural example of a solar cell.

FIG. 9 is a schematic view showing an example of a passivation device and an electrodeposition device.

FIG. 10 is a schematic view showing an example of a forming device.

FIG. 11 is a schematic view showing an example of a roll-to-roll system electrodeposition device.

FIG. 12 is a schematic view showing an example of a roll-to-roll system electrodeposition apparatus.

FIG. 13 is a graph showing changes in current during electrodeposition.

FIG. 14 is a graph showing the relationship between the voltage during electrodeposition and the conversion efficiency of the manufactured solar cell.

FIG. 15 is a graph showing the relationship between the current density during electrodeposition and the conversion efficiency of the manufactured solar cell.

FIG. 16 is a graph showing changes in current during electrodeposition.

FIG. 17 is a graph showing the change over time in voltage during electrodeposition.

FIG. 18 is a graph showing a change over time in current during electrodeposition.

FIG. 19 is a graph showing the relationship between the passivation voltage and the conversion efficiency of the manufactured solar cell.

FIG. 20 is a graph showing the relationship between the voltage during electrodeposition and the conversion efficiency of the manufactured solar cell.

FIG. 21 is a diagram showing the characteristics of the solar cell of Example 41 at the initial stage and after the reliability test (conversion efficiency).

22 is a diagram showing the characteristics of the solar cell of Example 41 after the initial test and after the reliability test (shunt resistance). FIG.

23 is a diagram showing the characteristics of the solar cell of Example 42 in the initial stage and after the reliability test (conversion efficiency). FIG.

FIG. 24 is a diagram showing characteristics of the solar cell of Example 42 in the initial stage and after the reliability test (shunt resistance).

FIG. 25 is a diagram showing characteristics of the solar cell of Example 43 in the initial stage and after the reliability test (conversion efficiency).

FIG. 26 is a diagram showing the characteristics of the solar cell of Example 43 at the initial stage and after the reliability test (shunt resistance).

FIG. 27 is a graph showing the relationship between the current density during electrodeposition and the conversion efficiency of the manufactured solar cell.

28 is a diagram showing the characteristics of the solar cell of Example 44 in the initial stage and after the reliability test (conversion efficiency). FIG.

FIG. 29 is a diagram showing the characteristics of the solar cell of Example 44 initially and after a reliability test (shunt resistance).

FIG. 30 is a diagram showing characteristics of the solar cell of Example 45 in the initial stage and after the reliability test (conversion efficiency).

FIG. 31 is a diagram showing the characteristics of the solar cell of Example 45 at the initial stage and after the reliability test (shunt resistance).

FIG. 32 is a graph showing changes in current during electrodeposition.

FIG. 33 is a graph showing the relationship between the voltage during electrodeposition and the conversion efficiency of the manufactured solar cell.

[Explanation of symbols]

 100 solar cell main body 101 substrate 102 lower electrode 103, 113, 123 n layer 104, 114, 124 i layer 105, 115, 125 p layer 106 upper electrode 107 grid electrode 108 bus bar 109 defective portion 110 electrodeposition film 301 electrolytic cell 302 electrolysis Liquid 303 Counter electrode 304 Substrate 305 Semiconductor layer 306 Power supply 307 Conductive wire 401 Stage 402 Solar cell 403 Conductive brush 404 Rail 405 Power supply 406 Conductive wire 501 Substrate 502 Substrate feeding roller 503 Substrate take-up roller 504, 514 Electrolytic bath 505, 515 Cleaning bath 506 516 Drying furnace 507, 517 Power supply 508, 518 Mask film feeding roller 509, 519 Mask film take-up roller 510, 520 Mask film 511, 52 Counter electrodes 512 and 522 conductive roller.

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Takahiro Mori 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Soichiro Kawakami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (19)

[Claims] 1. A solar cell in which a semiconductor layer having at least one junction and an electrode are laminated on a conductive substrate, and a defective portion having a low resistance is selectively insulation-coated with an electrodeposition resin to improve shunt resistance. A solar cell characterized by having a resistance of 1 × 10 ³ Ωcm ² or more. 2. The solar cell according to claim 1, wherein the electrodeposition resin is provided on the electrode. 3. The solar cell according to claim 1, wherein the electrodeposition resin is provided between the electrode and the semiconductor layer. 4. The solar cell according to claim 1, wherein the electrode of the defective portion is selectively removed, and the removed portion is covered with an electrodeposition resin. 5. The size of the electrodeposition resin is not more than 10 times the size of the defective portion, and the size of the electrodeposition resin is less than 10 times.
The solar cell according to any one of 1. 6. The solar cell according to claim 1, wherein the electrodeposition resin is transparent. 7. The electrodeposition resin contains at least one of acrylic resin, epoxy resin, fluororesin, urethane resin, and polybutadiene resin.
The solar cell according to claim 1. 8. The solar cell according to claim 1, wherein the minimum film formation temperature of the electrodeposition resin is 50 ° C. or higher. 9. The glass transition point of the electrodeposition resin is 100 ° C.
It is above, It is any one of Claims 1-8 characterized by the above-mentioned.
The solar cell according to the item. 10. A method of manufacturing a solar cell comprising a conductive substrate, and a semiconductor layer having at least one junction and an electrode, which are laminated on each other, wherein an electrodeposition resin film is selectively formed on a defective portion after the semiconductor layer is formed. Is formed, and then the electrode is formed. 11. A method of manufacturing a solar cell, which comprises a semiconductor layer having at least one junction and an electrode laminated on a conductive substrate, wherein the semiconductor layer and the electrode are sequentially formed, and then a defect portion is selectively formed. A method for manufacturing a solar cell, which comprises forming an electrodeposition resin film. 12. The method of manufacturing a solar cell according to claim 11, wherein the electrode of the defective portion is removed after the electrode is formed and before the electrodeposition resin film is formed. 13. The method for manufacturing a solar cell according to claim 11, wherein after forming the electrodes, forming is performed by applying an electric field before removing the electrodes of the defective portion. 14. The method of manufacturing a solar cell according to claim 10, wherein the electrodeposition is performed by applying a reverse bias equal to or lower than a breakdown voltage of the solar cell. 15. The electrodeposition is performed by applying a forward bias so that the forward current of the solar cell is not more than twice the shunt current. A method for manufacturing a solar cell according to item. 16. The method for manufacturing a solar cell according to claim 10, wherein the electrodeposition resin is transparent. 17. The electrodeposition resin according to claim 10, wherein the electrodeposition resin contains at least one of acrylic resin, epoxy resin, fluororesin, urethane resin, and polybutadiene resin. Method for manufacturing solar cell. 18. The minimum film forming temperature of the electrodeposition resin is 50 ° C.
It is above, The manufacturing method of the solar cell of any one of Claims 10-17 characterized by the above-mentioned. 19. The glass transition point of the electrodeposition resin is 100.
The temperature is not lower than 0 ° C, and the method for manufacturing a solar cell according to any one of claims 10-18.