JP2002246616A - Method of manufacturing photoelectric conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a photoelectric conversion device which prevents a fused resin from being adhered to the surface of a substrate in a laminating process to eliminate a resin removal work from the surface of the substrate, and can manufacture the device while flaws are prevented from being made on the surface of the substrate due to the contact of the substrate with a support member or the like in a curing process. SOLUTION: A method for manufacturing a photoelectric conversion device has a process for stacking a paper (52), a glass substrate (50) formed with a photoelectric conversion element (51), a sealing resin sheet (53), and a protective sheet (54) on a laminator press (4) and for fusing the sheet (53) for laminate. (54); and a process for holding the paper (52) by the sheet (53) through the laminating process on a support member (41), and for supporting the substrate (50) laminated with the sheets (53) and (54) on the member (41) in a state that the substrate (50) is stacked on the element (51) to heat the sheet (53) within a curing device to cure the sheet (53).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a photoelectric conversion device, and more particularly to a method for laminating a sealing resin / protective sheet for sealing a photoelectric conversion element formed on a substrate and a step for curing a sealing resin. Regarding improvement.

[0002]

2. Description of the Related Art Photovoltaic devices, for example, solar cell modules, include a crystal type using a silicon crystal and a thin film type using an amorphous silicon thin film or a polysilicon thin film. For example, a thin-film type solar cell module having a superstrate structure is a string-shaped multi-stage photoelectric conversion element (solar cell) composed of a transparent electrode layer, a photoelectric conversion semiconductor layer, and a back electrode layer laminated on the back surface of a glass substrate. Are connected in series. In any case, the problem is that silicon itself easily undergoes a chemical reaction and is vulnerable to physical impact.
Therefore, for the purpose of protecting silicon and the like, the photoelectric conversion element formed on the substrate of the solar cell module is sealed with ethylene-vinyl acetate copolymer (hereinafter referred to as EVA) containing a crosslinking agent as a main component. A structure sealed with a protective sheet using resin and Tedlar is employed.

Conventionally, a step of resin-sealing a solar cell module has been performed using a laminator as follows. That is, the substrate on which the photoelectric conversion element is formed, the sealing resin, and the protective sheet are placed on the laminator press section in a state of being stacked. An endless belt made of a glass cloth impregnated with a fluorine resin (for example, Teflon manufactured by DuPont) is used in the laminator press section, and the substrate is transported to a predetermined position by the rotation of the belt. Then, the sealing resin was melted by heating with a heater plate provided at the lower part of the laminator, and lamination was performed by applying pressure from above through a diaphragm.

As described in Japanese Patent Application Laid-Open No. 9-70886, the use of a glass cloth belt impregnated with a fluororesin in the laminator press section as described above is intended to maintain the strength of the belt while maintaining the strength of the molten resin. It is intended to prevent the resin from remaining in the laminator press part by utilizing the poor wettability of the fluororesin to the resin. However, the adhesion of the resin to the laminator press cannot be completely prevented, and the resin remaining in the laminator press moves to and adheres to the substrate at the next press on the solar cell module. Also, during the pressing, the molten resin may flow, enter through the gap between the laminator press section and the substrate, and adhere to the substrate surface. For this reason, it is necessary to clean and wash the laminator press part, and to remove the resin that has adhered to the substrate surface by using, for example, a metal tool or wiping it off with alcohol. It was hanging. Further, when a light reflecting film (AR coating) is formed on the substrate surface, it is extremely difficult to remove the adhered resin without damaging the surface due to the low hardness of the light reflecting film.

In order to solve such problems, attempts have been made to adjust the amount of sealing resin or to change the material of the laminator press section, but these methods have not been effective solutions. Was.

[0006] As a step subsequent to the laminating step, a substrate on which a sealing resin and a protective sheet are laminated with respect to the photoelectric conversion element is supported on a supporting member, and the sealing resin is crosslinked by heating in a curing device. Then, a step of curing (curing) is performed.

In this step, when the substrate is set on the support member, the substrate surface is damaged due to contact with the support member or the like, and particularly when the antireflection film is provided, the damage is remarkable. Had to be a problem.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to prevent a molten resin from adhering to a substrate surface in a laminating process of a sealing resin and a protective sheet included in a photoelectric conversion device manufacturing process, and An object of the present invention is to provide a method capable of eliminating a resin removing operation. Another object of the present invention is to provide a method capable of preventing a substrate surface from being damaged due to contact with a support member in a curing step of a sealing resin included in a manufacturing process of a photoelectric conversion device.

[0009]

According to a method of manufacturing a photoelectric conversion device according to the present invention, paper, a substrate on which photoelectric conversion elements are formed, a sealing resin, and a protective sheet are laminated on a laminator press section. It is characterized in that it is installed in a state, and the sealing resin is melted and laminated.

In another method for manufacturing a photoelectric conversion device according to the present invention, a paper and a substrate on which a sealing resin and a protective sheet are laminated on a photoelectric conversion element are supported on a support member in an overlapping state. And heating the sealing resin by heating in a curing device.

According to still another method of manufacturing a photoelectric conversion device according to the present invention, a paper, a substrate on which a photoelectric conversion element is formed, a sealing resin, and a protective sheet are placed on a laminator press section in a stacked state. Then, a step of melting and laminating the sealing resin, and on a support member, paper is held by the sealing resin through a laminating step, and the sealing resin and the protective sheet are laminated on the photoelectric conversion element. Supporting the stacked substrates in a stacked state, and heating the sealing resin by heating in a curing device.

In the present invention, an antireflection film may be formed on the substrate.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the type of a photoelectric conversion device, for example, a solar cell module is not particularly limited, and may be a crystal type or a thin film type. For example, a thin-film type solar cell module having a superstrate structure is a string-shaped multi-stage photoelectric conversion element (solar cell) composed of a transparent electrode layer, a photoelectric conversion semiconductor layer, and a back electrode layer laminated on the back surface of a glass substrate. Are connected in series, and sunlight enters through the glass substrate. Examples of the structure of the photoelectric conversion semiconductor layer include pin-type amorphous silicon, pin-type polysilicon, a hybrid of pin-type amorphous silicon and pin-type polysilicon, and the like.

An antireflection film (AR coating) may be formed on the surface of the glass substrate. As the antireflection film, for example, a film in which silica particles are dispersed in an inorganic polymer made of an alkyl silicate, or an organic polymer particle in a hydrolyzable silyl group-containing acrylic copolymer or a hydroxyl group-containing fluororesin A film having fine irregularities formed on the surface of the formed film is used.

The present invention is characterized in that a paper is laid under the substrate in the laminating step of the sealing resin / protective sheet and / or the curing step of the sealing resin included in the photoelectric conversion device manufacturing process. As the paper, for example, straw half paper is used.

In one embodiment of the present invention, in a laminating step of the sealing resin included in the manufacturing process of the photoelectric conversion device, paper, a substrate on which the photoelectric conversion element is formed, a sealing resin, Then, the protective sheet is placed in an overlapping state, and the sealing resin is melted and laminated. At this time, paper larger than the substrate is used, and the periphery of the substrate is surrounded by the paper.

According to this method, since the paper exhibits good wettability with respect to the molten resin, even if the molten resin flows when pressed by the laminator, the molten resin is absorbed by the paper around the substrate and is absorbed by the paper. It is possible to prevent the molten resin from adhering to the surface of the substrate without stopping at the edge and moving inward. For this reason, unlike the related art, there is no need to perform an operation for removing the resin that has adhered to the substrate surface and solidified. Therefore, even when an anti-reflection film is formed on the substrate surface, scratches can be prevented, the product yield can be increased, and the commercial value can be increased. Therefore, the industrial value is extremely large.

As is apparent from the above description, in principle, if a sheet showing good wettability to the molten resin is laid under the substrate, the resin can be prevented from adhering to the substrate surface. . Therefore, not only paper, but also a resin sheet (for example, Tedlar manufactured by DuPont) showing good wettability to molten resin by surface treatment can be used. However, paper such as straw paper is extremely superior in cost as compared with resin sheets.

In another embodiment of the present invention, in the curing step of the sealing resin included in the manufacturing process of the photoelectric conversion device,
Paper and a substrate on which a sealing resin and a protective sheet are laminated with respect to the photoelectric conversion element are supported on a support member in an overlapping state, and the sealing resin is cured by heating in a curing device.

In this method, since the substrate is supported on the support member with the paper interposed therebetween, it is possible to prevent the surface of the substrate from being damaged during the installation work on the support member. In particular, even when an anti-reflection film is formed on the substrate surface, it can be prevented from being damaged, and the product yield and the commercial value can be increased.

In still another embodiment of the present invention, in a laminating step of a sealing resin, a paper, a glass substrate on which a photoelectric conversion element is formed, a sealing resin, and a protective sheet are laminated on a laminator press section. In a state where the sealing resin is melted and laminated, and subsequently, in the sealing resin curing step, the paper is held by the sealing resin through the laminating step on the support member, and with respect to the photoelectric conversion element. The substrates on which the sealing resin and the protective sheet are laminated are supported in an overlapping state, and heated in a curing device to cure the sealing resin.

In this method, since the paper is laid under the substrate through the laminating process and the curing process, the molten resin is prevented from adhering to the substrate surface and the substrate surface is protected during the operation, and the substrate surface is not damaged. Can be prevented very effectively.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The laminator used in the laminating step will be described with reference to FIGS. FIG. 1 is a front view of the laminator, and FIG. 2 is a side view. At one end of the laminator apparatus main body 1, a pair of drive rollers 2 are provided at predetermined intervals vertically, and at the other end, a pair of driven rollers 3 are provided at predetermined intervals vertically. An endless belt 4 forming a laminator press section is stretched between the driving roller 2 and the driven roller 3. The endless belt 4 is made of Teflon-coated glass nonwoven fabric. The drive roller 2 is driven to rotate by a drive source 5, whereby the endless belt 4 runs endlessly. A receiving member 6 for preventing the belt 4 from bending downward is provided at a portion between the driving roller 2 and the driven roller 3 on the lower surface of the belt 4. On the upper surface of the receiving member 6, a heater plate 7 is provided.

A column 21 is provided upright in the middle of the apparatus main body 1. A movable body 22 having a planar shape sufficiently larger than the glass substrate of the solar cell module is provided on the support 21,
It is provided so as to be driven vertically by a drive source 23. The movable body 22 is formed in a container shape with an open lower surface, and a rubber diaphragm 24 is hermetically provided at a position above the lower surface by a predetermined dimension from the lower end surface. An airtight upper chamber is formed.

The solar cell module includes a carry-in roller 31.
After being placed on the endless belt 4 and conveyed to a press section below the movable body 22 and passing through a predetermined laminating step,
From the endless belt 4, it is placed on the carry-out roller 32 and carried out.

At this time, as shown in FIG. 3, the glass substrate 50 on which the photoelectric conversion elements 51 are formed is placed on the straw paper 52, and the sealing resin sheet 53 and the protection sheet 54 are stacked on the photoelectric conversion elements 51. The laminate 55 is set. Since the straw half paper 52 is laid under the glass substrate 50 in this way, the glass substrate 50 is protected by the straw half paper 52 even if the straw half paper 52 comes into contact with the rollers 31 and 32 during loading and unloading.

The glass substrate 50 has a size of, for example, 910 m.
It has a size of mx 455 mm and a thickness of 4 mm. A scribed transparent electrode made of SnO ₂ having a thickness of about 0.8 μm is formed on the back surface. On top of that, a thickness of about 0.2
5 μm pin type amorphous silicon and a thickness of about 2
A scribed photoelectric conversion semiconductor layer made of μm pin-type polysilicon is formed. A scribed back electrode made of ZnO having a thickness of about 800 ° and Ag having a thickness of about 0.3 μm is formed thereon. Also,
On the light incident surface of the glass substrate 50, a light reflection film is formed. EVA containing a cross-linking agent is used for the sealing resin sheet 53. As the protective sheet 54, a sheet in which a fluororesin sheet (for example, Tedlar of DuPont) is bonded to both sides of an aluminum foil is used.

FIG. 4 is a plan view of the solar cell module transferred to the press position of the laminator. In this figure, members provided on the upper part of the laminator, such as the support 21 and the movable body 22, are omitted.

As shown in FIG. 3 and FIG.
Is larger than the glass substrate 50, and the distance from the edge of the glass substrate 50 to the edge of the outer straw half paper 52 is about 50 mm. The sealing resin sheet 53 (not shown in FIG. 4) is slightly smaller than the glass substrate 50, and the distance from the edge of the glass substrate 50 to the edge of the inner sealing resin sheet 53 is 2-3 m.
m. The protection sheet 54 is larger than the glass substrate 50, and is located outside the edge of the glass substrate 50.
Is about 20 to 30 mm.

Thereafter, as shown in FIG. 5, the movable body 22 is lowered to surround the laminated body 55 shown in FIG. 3 (only the straw half paper 52 and the glass substrate 50 are shown in FIG. 5 for simplicity). The upper surface of the belt 4 is covered by the lower end surface of the peripheral wall surface of the movable body 22. In this state, an airtight upper chamber 25 is formed above the diaphragm 24, and an airtight lower chamber 26 is formed between the lower surface of the diaphragm 24 and the upper surface of the belt 4. A first vacuum pump 27 and a second vacuum pump 28 are connected to the upper chamber 25 and the lower chamber 26, respectively.

In this state, the sealing resin sheet and the protective sheet are laminated as follows. The glass substrate 50, the sealing resin sheet 53, and the protection sheet 54 are heated by the heater plate 7 via the belt 4. First and second
Are operated to reduce the pressure in the upper chamber 25 and the lower chamber 26 at the same pressure. By this operation, the glass substrate 50 located on the belt 4 and the sealing resin sheet 53
Air is removed from the bonding surface of the sealing resin sheet 53 and the protection sheet 54 and the sealing resin sheet 5.
3 are removed. At this time, the upper chamber 25
Since the pressure in the lower chamber 26 is the same as that in the lower chamber 26, the diaphragm 24 hardly deforms.

Next, the pressure in the upper chamber 25 is released to communicate with the atmosphere. As a result, the diaphragm 24 expands and deforms toward the lower chamber 26 having a lower pressure, and presses the protective sheet 54 and the sealing resin sheet 53 stacked on the glass substrate 50. By this operation, the molten sealing resin adheres to the back surface of the glass substrate 50, and the sealing resin and the protection sheet 54 are laminated.

At this time, the molten resin protrudes from the peripheral portion of the glass substrate 50 and flows. However, since the straw paper 52 is laid under the glass substrate 50, the molten resin is absorbed by the straw paper 52 around the glass substrate 50, wraps around the edge of the glass substrate 50, and adheres to the surface thereof. There is no. Further, since the molten resin is absorbed by the straw paper 52, the molten resin does not move to the belt 4.

Thereafter, the pressure in the lower chamber 26 is released to communicate with the atmosphere. As a result, the pressure applied to the diaphragm 24 is removed, and the pressurizing operation ends. After the pressurization, the movable member 22 is raised, the belt 4 is intermittently driven by a predetermined distance, the glass substrate 50 on which the sealing resin sheet 52 is laminated is carried out of the apparatus body 1, and a new glass substrate 50 is carried in. Then, the above-described steps are repeated.

For comparison, a laminating step was performed in the same manner as described above, except that no straw half paper was provided between the belt and the glass substrate surface.

Similarly, for comparison, a Teflon sheet was provided between the belt and the surface of the glass substrate instead of the straw semi-paper, and the laminating step was performed in the same manner as described above. Teflon sheets have poor wettability to EVA.

Table 1 below shows the results of comparing the state of adhesion of the resin to the glass surface and the state of adhesion of the resin to the belt by the method of the embodiment using straw half paper and the method of the two comparative examples.

As shown in Table 1, when the laminating step was performed by laying straw semi-paper under the glass substrate, no adhesion of the resin to both the glass and the belt was observed.

[0040]

[Table 1]

After the above-mentioned laminating step, the straw half paper 53 is held under the glass substrate 50 by the sealing resin solidified at the edge of the glass substrate 50 carried out from the laminator.

After the laminating step, a sealing resin curing step is performed. This curing step is performed as follows. First, for example, as shown in FIG. 6, the laminated body 55 having undergone the laminating step is placed on a multi-stage shelf provided at the inner end of the cassette 40 having a size of about 1 m × 1 m × 1 m with the straw half paper 52 side down. It is installed on a support member 41 having a shape. 6 shows only the straw half paper 52 and the glass substrate 50 by simplifying the laminate 55 of FIG. At this time, since the straw half paper 52 is held under the glass substrate 50, it is possible to prevent the surface of the glass substrate 50 from being damaged even if the straw half paper 52 is rubbed with the support member 41.

The cassette 40 in which the laminated body 55 is set as described above is loaded into a curing device (heating furnace), and the sealing resin is cross-linked by heating and cured (cured). Heating in the curing apparatus is performed for about 1 hour in total, including raising the temperature, holding at about 150 ° C. for 10 to 20 minutes, and lowering the temperature.

After the curing step, the cassette 40 is taken out of the curing device, and the laminate 55 is removed from the cassette 40. Also at this time, since the straw half paper 52 is held under the glass substrate 50, it is possible to prevent the surface of the glass substrate 50 from being damaged even if it is rubbed with the support member 41.

Thereafter, the protective sheet 54 is placed on the glass substrate 50.
Cut according to the size of (trimming). At this time, the straw half paper 52 held under the glass substrate 50 is also peeled off.

The types of the laminator and the curing device are not particularly limited, and those other than those described above can be used. For example, the loading of the glass substrate 50 into the curing device is not limited to the one using the cassette 40 as described above, but may be a type using a roller or a belt.

In the above description, an example was described in which the same straw paper was laid under the substrate through the laminating process and the curing process to perform the work. May be laid. Even in such a case, a desired effect can be obtained in each step. For example, when using a laminator that does not cause a problem of adhesion of the resin to the substrate surface, a straw semi-paper may be laid under the substrate only in the curing step.

[0048]

As described above in detail, the use of the method of the present invention prevents the molten resin from adhering to the substrate surface in the laminating step of the sealing resin / protective sheet included in the photoelectric conversion device manufacturing process. The operation of removing the resin from the substrate surface can be eliminated, and the surface of the substrate can be prevented from being damaged due to contact with the support member or the like in the curing step of the sealing resin included in the manufacturing process of the photoelectric conversion device.

[Brief description of the drawings]

FIG. 1 is a front view showing a laminator used in an embodiment of the present invention.

FIG. 2 is a side view of the laminator of FIG. 1;

FIG. 3 is a front view showing a laminate of a straw semi-paper, a glass substrate, a sealing resin sheet, and a protection sheet installed on a laminator.

FIG. 4 is a plan view showing a state where a solar cell module is installed in a press section of the laminator of FIG. 1;

FIG. 5 is a view for explaining a laminating step using the laminator in FIG. 1;

FIG. 6 is a front view showing a cassette inserted into a curing device used in one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Device main body 2 ... Drive roller 3 ... Follower roller 4 ... Endless belt 5 ... Drive source 6 ... Receiving member 7 ... Heater plate 21 ... Post 22 ... Movable body 23 ... Drive source 24 ... Diaphragm 31 ... Import roller 32 ... Export roller DESCRIPTION OF SYMBOLS 40 ... Cassette 41 ... Support member 50 ... Glass substrate 51 ... Photoelectric conversion element 52 ... Straw half paper 53 ... Sealing resin sheet 54 ... Protective sheet 55 ... Laminate

Claims (4)

[Claims] 1. A laminator press section in which a paper, a substrate on which a photoelectric conversion element is formed, a sealing resin, and a protective sheet are placed in an overlapping state, and the sealing resin is melted and laminated. A method for manufacturing a photoelectric conversion device, comprising: 2. A method in which a paper and a substrate on which a sealing resin and a protective sheet are laminated with respect to a photoelectric conversion element are supported on a supporting member in an overlapping state, and the sealing resin is heated in a curing device. Curing the photoelectric conversion device. 3. A step in which a paper, a substrate on which a photoelectric conversion element is formed, a sealing resin, and a protective sheet are stacked on a laminator press section, and the sealing resin is melted and laminated. And a support member on which a paper sheet is held by the sealing resin through a laminating step, and a substrate on which the sealing resin and the protective sheet are laminated is supported on the photoelectric conversion element in a stacked state, and the inside of the curing device And curing the sealing resin by heating at a temperature in the step (c). 4. The method according to claim 1, wherein an anti-reflection film is formed on the substrate.