JPH06310748A - Solar cell module - Google Patents

Abstract

PURPOSE:To provide a large scale solar cell module which can be manufactured at low cost while keeping high reliability. CONSTITUTION:A first electrode layer of conductive metal oxide, an amorphous semiconductor layer, a second electrode layer of metal, and at least one of a dielectric layer 6 or a sealing resin layer 7 having principal chain skeleton of polyisobuthylene are laminated sequentially on a trans parent substrate of tempered glass or laminated glass.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-sized amorphous semiconductor solar cell module, and more particularly to an amorphous semiconductor solar cell module in which the entire solar cell can be sealed by a simple method and is excellent in strength. Is.

[0002]

2. Description of the Related Art Amorphous semiconductor solar cells such as amorphous silicon have a higher degree of freedom in substrate selection than crystalline semiconductor solar cells, and have relatively low temperatures on glass substrates, metal substrates, resin substrates, etc. It has a feature that it can be easily formed by. Therefore, in a relatively small solar cell module, a conductive metal oxide layer, an amorphous semiconductor layer, and a metal layer are formed on a glass substrate, and a sheet-shaped resin is sealed by vacuum lamination with an adhesive layer sandwiched between them. Is formed.

On the other hand, the large-sized solar cell module which is the subject of the present invention needs to be reinforced in terms of strength, and a conductive metal oxide layer, an amorphous layer, an amorphous layer, a glass substrate, a tempered glass or a laminated glass. It is formed by arranging a plurality of so-called solar cell submodules each having a semiconductor layer and a metal layer formed thereon, electrically connecting them, and then sandwiching and sealing them with a sheet-shaped resin. FIG. 6 shows an example of a large-sized amorphous silicon solar cell module in the prior art as a sectional structure view. The example of this figure is based on the super straight method, which has been generally used in the past, and includes a plurality of electrically connected copper foils 13 and the like with a white plate tempered glass 1 and a filler 11 such as ethylene vinyl acetate. One solar cell sub-module 10, 10 ...
Is sealed and the aluminum foil sandwich type vinyl fluoride film 12 and the like are laminated as a protective film.
For sealing the solar cell submodule 10 with the filler 11, a vacuum laminating method is usually used.

[0004]

As described above, when forming a large-sized solar cell module, in addition to the step of forming the solar cell sub-module, the arrangement and electrical connection of the solar cell sub-module on the tempered glass are performed. In addition to the large number of man-hours such as laminating by the vacuum process, an expensive vacuum device such as a laminating device is required, and the unit price of the product increases, which is a price problem, and air bubbles in the filling material during laminating. There was a quality problem such as mixing. Further, there is a problem in characteristics that module efficiency is lowered because a gap is generated between the sub-modules. That is,
In the prior art, although amorphous silicon, which is originally advantageous for cost reduction, is used, it must be reinforced with tempered glass or laminated glass due to strength requirements, so an inexpensive solar cell module cannot be provided. There are drawbacks in terms of cost, quality defects in which air bubbles are mixed in the filler during the manufacturing process, which also lowers reliability, and performance defects, such as lower module efficiency.

[0005]

The present invention has been devised in view of the above-mentioned problems, and a large amorphous semiconductor solar cell module can be manufactured at low cost while maintaining high reliability. According to the first aspect of the present invention, there is provided an amorphous semiconductor solar cell module formed on a glass substrate, which comprises a tempered glass or a laminated glass and a conductive metal oxide. A layer, an amorphous semiconductor layer, a metal layer, an insulator layer, and a sealing resin layer are sequentially laminated, or a tempered glass or a laminated glass,
A conductive metal oxide layer, an amorphous semiconductor layer, a metal layer,
One of the insulating layer and the sealing resin layer is sequentially laminated, and the insulating layer is a layer containing silicon oxide having a thickness of 0.01 μm or more, The water vapor permeability after curing is 1 g / m ² · day or less at a layer thickness of 100 μm, and the layer thickness is 0.
It is also considered that the resin is a polyisobutylene-based resin of 05 mm or more. In addition, such means for solving the problem is particularly effective for a solar cell module having a light-receiving surface area of 0.1 m ² or more.

A feature of the second invention is that it is formed by sequentially laminating a first electrode layer, an amorphous semiconductor layer, a second electrode layer, and a sealing resin layer on a transparent substrate. In the solar cell module, the main chain skeleton of the sealing resin layer is polyisobutylene.

[0007]

The solar cell module of the present invention forms a solar cell made of an amorphous semiconductor directly on tempered glass, laminated glass or other transparent substrate, and has an insulating layer containing silicon oxide and a main chain skeleton. The back surface is protected by providing a sealing resin layer which is polyisobutylene and has a low water vapor transmission rate.

[0008]

EXAMPLES The present invention will be described below based on examples.
FIG. 1 is a schematic view of an embodiment of the solar cell module of the present invention. In the figure, 1 is a glass substrate, 5 is a solar cell element in which a conductive metal oxide layer, an amorphous semiconductor layer, and a metal layer are sequentially laminated, 6 is an insulator layer, and 7 is a sealing resin layer. As the conductive metal oxide layer, tin oxide or indium tin oxide is used as in the conventional solar cell module. Amorphous silicon is used for the amorphous semiconductor layer, and a laminated structure of chromium and aluminum is used for the metal layer.

As the glass substrate 1, a tempered glass, a laminated glass, or another general transparent substrate is used, and a glass substrate to which silicon oxide or the like is adhered may be used so that the glass component is not eluted. .

In order to prevent the metal layer from being corroded by oxygen even under conditions of high temperature and high humidity, it is preferable to use silicon oxide as the insulator layer 6 because it has a low oxygen transmission rate and can be produced at a temperature lower than the film formation temperature of amorphous silicon. It is suitable, and the film thickness is preferably 0.01 μm or more, more preferably 0.05 μm or more. Further, as a manufacturing method, a sputtering method, a resistance heating evaporation method, an electron beam evaporation method, an optical CVD
Method, spin-on method, etc. are used, but other methods such as dip method, spray method, etc. are also possible.
If the film thickness is 01 μm or more, the oxygen permeability is 0.0
It becomes about 1 (cc · mm / m ² · day · atm),
The expected shielding effect can be obtained. On the other hand, if the film thickness is 1 μm or more, the oxygen permeability is saturated with an increase in the film thickness, so it is sufficient to set the film thickness to this film thickness or less. Further, since the present insulating layer is formed after the solar cell element is formed, the film forming temperature is equal to or lower than the solar cell manufacturing temperature.
The temperature is preferably 00 ° C or lower, and more preferably 150 ° C or lower.

As the encapsulating resin layer 7, a polyisobutylene-based resin disclosed in Japanese Patent Application Laid-Open No. 3-140316 by the present applicant is used. Also for this, the insulator layer 6
Similarly, in order to prevent the corrosion of the metal layer even under high temperature and high humidity conditions, it has a water vapor shielding effect.
The water vapor permeability of the sealing resin layer 7 is about 0.1 (g / m ² · day) at a film thickness of 200 μm, and the film thickness is preferably 0.05 mm or more, and further 0.1 mm.
It is preferably 1.0 mm or less. It is also possible to add a filler such as silica, titanium dioxide, carbon black or talc.

The embodiments of the first invention will be described in more detail below, but the invention is not limited to these embodiments.

[Embodiment 1] In FIG.
After forming a tin oxide layer 2 as a conductive oxide layer to a thickness of about 500 nm on a tempered glass 1 produced by carrying out hot air cooling tempering having a size of 2 mm, 440 mm × 150 mm, as shown in FIG. As shown, YA with a wavelength of 1.06 μm
Using the fundamental wave of the G laser, the unit elements were electrically separated so that the width was 1 cm. At this time, the resistance value between the adjacent tin oxide layers was 1 MΩ or more.
After that, ultrasonic cleaning is performed with pure water, and monosilane and methane are applied to the surface on which the tin oxide layer 2 is deposited as shown in FIG. 3C at a substrate temperature of 200 ° C. and a reaction pressure of 0.5 to 1.0 Torr. , A mixed gas of diborane, monosilane, a mixed gas of hydrogen, a mixed gas of monosilane, phosphine, and hydrogen are decomposed in this order in a capacitively coupled glow discharge decomposition apparatus to form p as an amorphous semiconductor layer 3. -Type amorphous silicon semiconductor layer, i-type amorphous silicon semiconductor layer,
And the n-type microcrystalline silicon semiconductor layer were formed to have respective film thicknesses of 15 nm, 450 nm, and 300 nm. After cooling, shift by 50 μm from the separated portion of the tin oxide layer,
As shown in FIG. 3D, the pin amorphous silicon semiconductor layer 3 has a wavelength of 0.
Separation was performed using the second harmonic of a 53 μm YAG laser. Thereafter, by electron beam evaporation, aluminum was formed to a thickness of 250 nm as a metal layer to form the back electrode 4 as shown in FIG. After removing the sample from the vapor deposition apparatus, as shown in FIG. 6F, the sample is shifted further by 50 μm from the separated portion of the amorphous silicon semiconductor layer so that the amorphous silicon semiconductor layer 3 and the tin oxide layer 2 are not damaged. The back electrode layer 4 on the second YAG laser with a wavelength of 0.53 μm.
The integrated type amorphous silicon solar cell was manufactured by removing it using harmonics. The separation width by laser scribing was about 50, 150, and 150 μm for the tin oxide layer, the amorphous silicon semiconductor layer, and the back electrode layer, respectively.

The solar cell thus obtained was measured under irradiation with pseudo sunlight having an air mass of 1.5 and 100 mw / cm ² , and an output of about 4 W was confirmed. On the back electrode 4 of this solar cell, a heat-resistant polyester tape was used to mask only the lead wire extraction portion, and sputtering was performed using silicon oxide as a target to form an insulator layer 6. As the sputtering conditions, the AC sputtering method was 13.56 MHz, the substrate temperature was room temperature, the reaction pressure was 1.2 torr, and the argon gas flow rate was 20.
Sccm, input power was 100 w, and a film thickness of 40 nm was obtained in a film forming time of 5 minutes. Further, a resin layer containing polyisobutylene as a main component was applied and formed, and heat-cured at 130 ° C. for about 2 hours to obtain a sealing resin layer 7 having a film thickness of 200 μm. After removing the resin from the electrode extraction portion, the lead wire was taken out by soldering, polyisobutylene was further applied to the resin-removed portion, and heat curing was performed at 130 ° C. for 2 hours. After cooling, the end surface of the solar cell panel P thus produced was fitted and fixed to the aluminum frame 8 using the butyl rubber adhesive 14 to complete the solar cell module as shown in FIG. When this solar cell module was measured under irradiation of pseudo sunlight with an air mass of 1.5 and 100 mw / cm ² , an output of 4 W was obtained, and the characteristics of the back electrode 4 were deteriorated due to the bombardment of vapor deposition particles by the sputtering method. Although initially thought, under the above conditions, no characteristic deterioration was observed, and no characteristic deterioration was observed in the process by sputtering and application of the polyisobutylene resin.

[Embodiment 2] Similar to Embodiment 1, the thickness 3.
A solar cell having a size of 2 mm and a substrate size of 440 × 150 mm was manufactured, and a silicon oxide film was further formed as an insulator layer by a sputtering method. After that, the polyester tape used for masking is removed, the lead wire is taken out by soldering, and then polyisobutylene is applied to a portion around the lead wire takeout part where the silicon oxide film is not present and the temperature is about 2 ° C. at 130 ° C.
Heat cured for hours. After cooling, the end surface of the solar cell panel thus produced was fitted and fixed to an aluminum frame using a butyl rubber adhesive to complete the solar cell module. When this solar cell module was measured under pseudo sunlight with an air mass of 1.5 and 100 mw / cm ² , an output of 4 W was obtained.

[Third Embodiment] Similar to the first embodiment, the thickness 3.
A solar cell having a size of 2 mm and a substrate size of 440 × 150 mm was manufactured, and a silicon oxide film was further formed as an insulator layer to a thickness of 50 nm in an oxygen atmosphere using an EB vapor deposition machine. After this, a resin layer containing polyisobutylene as a main component is formed by coating,
After thermosetting at 130 ° C. for about 2 hours, a sealing resin layer having a film thickness of 200 μm was obtained. After removing the resin from the electrode extraction portion, the lead wire was taken out by soldering, polyisobutylene was further applied to the resin-removed portion, and heat curing was performed at 130 ° C. for 2 hours. After cooling, the end surface of the solar cell panel thus produced was fitted and fixed to an aluminum frame using a butyl rubber adhesive to complete the solar cell module. This solar cell module is air mass 1.
When measured in 5,100 mw / cm ² of pseudo sunlight, an output of 4 W was obtained.

[Comparative Example 1] A solar cell element 10 having a back electrode formed on a glass substrate of 5 inches x 6 inches by the same method as in Example 1 was formed on a tempered glass 1 similar to Example 1. A 600 μm thick ethylene vinyl acetate (EVA) film 11, a solar cell element 10,
The same EVA film 11 and a polyvinyl fluoride resin (PVF) film (PVF) sandwiching aluminum foil
38 μm / Aluminum foil 30 μm / PVF 38 μm)
The layers 12 were laminated in this order, heated in a vacuum using a laminating method and subjected to a crosslinking treatment, and the output lead wires were taken out of the substrate to obtain a solar cell panel P. Except that the end surface of the solar cell panel P thus produced is fitted and fixed to the aluminum frame 8 using the butyl rubber adhesive 14 and the solar cell elements are not connected by a copper foil. A solar cell module having the same structure as that shown as the conventional example in 6 was completed.

In the above three examples, the substrate size was 5 inches × 6 inches, and the tempered glass had a thickness of 1.1 m.
Five solar cell modules each having m were produced for each example. In order to evaluate the reliability of this solar cell module, the tank temperature was 127 ° C., the tank pressure was 2 atm, and the relative humidity was 85% R.V. H. The pressure cooker test was performed for 500 hours. FIG. 4 shows the frequency distribution of the maximum output after 500 hours of the main test, which is standardized with the initial value. In the figure, the vertical axis represents the number of solar cell modules used in this test, and the horizontal axis represents η / η ₀ , which represents the conversion efficiency after the test with respect to the initial conversion efficiency of the solar cell module. Further, FIG. 5 shows a change in average conversion efficiency up to 500 hours of the main test, which is standardized with an initial value.

As is clear from FIGS. 4 and 5, in the solar cell module of the present invention, although a slight reduction in output was observed in Example 2 even in a pressure cooker test extremely harsh with respect to electronic parts, 500
It can be seen that there is almost no problem with the deterioration of the output after the elapse of time, and the reliability is improved as compared with the conventional technique. It is considered that the decrease in output seen in Example 2 does not result in large deterioration in actual outdoor exposure, considering the test conditions.

In the above-described embodiments, the one using both the insulating layer and the sealing resin layer and the one using only the insulating layer are shown, but it is also possible to use only the sealing resin layer.

Further, the details of the second invention will be described below based on specific embodiments. Figure 2 (a)
2B, after a tin oxide layer having a thickness of 3.2 mm and a size of 440 mm × 150 mm and having a thickness of about 500 nm was formed as a first electrode layer on the soda-lime glass by a thermal CVD method.
Similarly, a YAG laser fundamental wave having a wavelength of 1.06 μm was used to electrically separate the unit elements so that the width thereof was 1 cm. At this time, the resistance value between the adjacent tin oxide layers was 1 MΩ or more. After that, ultrasonic cleaning is performed with pure water, and a substrate temperature of 200 ° C. and a reaction pressure of 0.5 to 1.0 T are applied to the surface side on which the tin oxide layer is deposited, as in FIG.
By decomposing a mixed gas consisting of monosilane, methane and diborane, a mixed gas consisting of monosilane and hydrogen, a mixed gas consisting of monosilane, phosphine and hydrogen in this order in a capacity coupled glow discharge decomposition apparatus at As the semiconductor layer, a p-type amorphous silicon semiconductor layer, i
Type amorphous silicon semiconductor layers and n-type microcrystalline silicon semiconductor layers having respective film thicknesses of 15 nm, 450 nm, 3
It was formed to have a thickness of 00 nm. After cooling, the tin oxide layer was displaced by 50 μm from the separated portion, and pi was formed in the same manner as in FIG.
-N The amorphous silicon semiconductor layer is formed by a second YAG laser having a wavelength of 0.53 μm so as not to damage the tin oxide layer.
Separated using harmonics. Then, similarly to FIG. 3E, aluminum was formed as the second electrode layer to a thickness of 250 nm by electron beam evaporation to form a back electrode. After removing the sample from the vapor deposition apparatus, as in FIG.
50 μm further than the separated portion of the amorphous silicon semiconductor layer
The back electrode layer is shifted to a YA with a wavelength of 0.53 μm so as not to damage the amorphous silicon semiconductor layer and the tin oxide layer.
It was removed by using the second harmonic of G laser to manufacture an integrated amorphous silicon solar cell. The separation width by laser scribing is about 50, 150, and 150 μm for the tin oxide layer, the amorphous silicon semiconductor layer, and the back electrode layer, respectively.
Met.

When the solar cell thus obtained was measured under irradiation of pseudo sunlight having an air mass of 1.5 and 100 mw / cm ² , an output of about 4 W was confirmed. A resin layer whose main chain skeleton is polyisobutylene is applied and formed on the back electrode of this solar cell, and after thermosetting at 130 ° C. for about 2 hours,
A sealing resin layer having a film thickness of 200 μm was obtained. After removing the resin in the electrode extraction portion, the lead wire was taken out by soldering, the polyisobutylene resin was further applied to the resin-removed portion, and heat curing was performed at 130 ° C. for 2 hours. After cooling, the end surface of the solar cell panel thus produced,
A butyl rubber-based adhesive was used to fit and fix the aluminum frame to complete the solar cell module as shown in FIG. This solar cell module is used for air mass 1.
When measured under irradiation with pseudo sunlight of 5,100 mw / cm ² , an output of 4 W was obtained, and no characteristic deterioration in the process due to application of the polyisobutylene resin was observed.

In the above-mentioned second invention, the substrate of the example shown as the first embodiment in the above-mentioned first invention is made of soda lime glass, and the back surface is coated only with polyisobutylene resin. In the same way as the invention of the above, in order to evaluate the reliability, the temperature inside the tank is 127 ° C, the pressure inside the tank is 2 atm, and the relative humidity is 85%
R. H. The pressure cooker test was performed for 500 hours, but no decrease in output was observed, and the time-dependent change was exactly the same as in Example 1 of the first invention.

[0024]

As described above, according to the present invention, by forming an amorphous solar cell directly on a tempered glass, a laminated glass, or another transparent substrate, a plurality of conventional solar cells are formed. Since it is not necessary to arrange submodules, it is possible to realize an inexpensive solar cell module with high module efficiency. Further, in place of the conventional filler such as ethylene vinyl acetate, an insulating layer containing silicon oxide or a sealing resin layer whose main chain skeleton having a low water vapor transmission rate is polyisobutylene was used. As a result of eliminating quality problems such as inclusion of bubbles in the filling material and improving the effect of shielding oxygen and water vapor, it is possible to realize an extremely reliable amorphous solar cell module.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a sectional structure of a solar cell module according to the present invention.

FIG. 2 is an explanatory view showing a manufacturing process of an amorphous silicon solar cell element, in which (a) shows a conductive metal oxide layer after being formed.
(B) shows the state after the conductive metal oxide layer is separated, and (c) shows the state after the amorphous semiconductor layer is formed.

FIG. 3 is an explanatory diagram showing a manufacturing process of an amorphous silicon solar cell element, in which (d) shows a state after the amorphous semiconductor layer is separated.
(E) shows the state after the metal layer is formed, and (f) shows the state after the metal layer is separated.

FIG. 4 is an explanatory diagram showing, as a histogram, characteristic changes before and after a test when a pressure cooker test is performed on the solar cell modules in Examples and Comparative Examples of the present invention.

FIG. 5 is an explanatory diagram that graphically represents characteristic changes when a pressure cooker test is performed on the solar cell modules according to Examples and Comparative Examples of the present invention.

FIG. 6 is an explanatory diagram showing a cross-sectional structure of a solar cell module according to a conventional technique.

[Explanation of symbols]

 1 tempered glass, blue plate glass 2 tin oxide layer 3 amorphous silicon layer 4 back electrode layer 5 solar cell formed on tempered glass 6 insulator layer 7 sealing resin layer 8 frame 10 solar cell submodule 11 filler 12 vinyl fluoride Film 13 Copper foil 14 Butyl rubber adhesive P Solar cell panel

Front page continuation (72) Inventor Masakazu Ishido 28-16 Koyamaboriikecho, Kita-ku, Kyoto City, Kyoto Prefecture (72) Masanobu Izumina 1-60-1 Horinouchicho, Omiya City, Saitama Prefecture

Claims (8)

[Claims] 1. An amorphous semiconductor solar cell module formed on a glass substrate, which comprises tempered glass or laminated glass, a conductive metal oxide layer, an amorphous semiconductor layer, and a metal layer. A solar cell module, wherein an insulating layer and a sealing resin layer are sequentially laminated. 2. An amorphous semiconductor solar cell module formed on a glass substrate, which comprises tempered glass or laminated glass, a conductive metal oxide layer, an amorphous semiconductor layer, and a metal layer. A solar cell module, wherein one of an insulator layer and a sealing resin layer is sequentially laminated. 3. The solar cell module according to claim 1, wherein a layer containing silicon oxide is used as the insulating layer. 4. The solar cell module according to claim 3, wherein the insulating layer has a thickness of 0.01 μm or more. 5. The water vapor permeability of the sealing resin layer after curing is 1 g / m ² · day at a layer thickness of 100 μm.
It is the following, The solar cell module of Claim 1 or 2 characterized by the following. 6. The solar cell module according to claim 5, wherein the sealing resin layer is a polyisobutylene-based resin having a layer thickness of 0.05 mm or more. 7. The solar cell module according to claim 1, wherein the area of the light receiving surface is 0.1 m ² or more. 8. A solar cell module formed by sequentially stacking a first electrode layer, an amorphous semiconductor layer, a second electrode layer, and a sealing resin layer on a transparent substrate, wherein the sealing resin is used. A solar cell module, wherein the main chain skeleton of the layer is polyisobutylene.