JP2011023666A - Method of manufacturing solar battery module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a solar battery module increased in output current. <P>SOLUTION: The method of manufacturing the solar battery module 70 includes a step of forming a first electrode layer 11 on the first surface of a translucent substrate 1, a step of forming a semiconductor layer 12 on the first electrode layer 11, a step of forming a reflective and conductive film on the semiconductor layer 12 and on the second surface of the translucent substrate 1 by an in-line sputtering device 80, and a step of forming one or more solar battery modules 10, a second electrode 14, and a first reflecting part 14' by separating at least the first electrode layer 11 or the reflective and conductive film. In the step of forming the reflective and conductive film, the translucent substrate 1 is carried along the direction in which the current of the semiconductor layer flows by the in-line sputtering device 80. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a solar cell module.

  The top view of the solar cell module in the solar cell module which concerns on a prior art is shown in FIG. FIG. 6 is a cross-sectional view of the solar cell module 170 shown in FIG. Below, the solar cell module which concerns on a prior art is demonstrated using FIG.5 and FIG.6.

  In the solar cell module 170, a first electrode layer (transparent conductive film) 111, a semiconductor layer (photoelectric conversion layer) 112, and a second electrode layer (back electrode) 114 are sequentially stacked on a translucent substrate (transparent substrate) 101. Thereafter, the plurality of solar cells 110 are formed by dividing using a known laser patterning method. The plurality of solar cells 110 formed in this manner are sealed between the translucent substrate 101 and the protective material 155 by a sealing material (filler) 150, and the end portions of the sealed solar cells 110 are sealed. The metal frame 165 is fixed through the resin 160 (see Patent Document 1). In FIG. 3, the sealing material 150 and the protective material 155 are omitted.

  In such a solar cell 110, an electron-hole pair generated in the semiconductor layer 112 by light incident from the translucent substrate 101 side is converted into a first electrode layer 111 and a second electrode layer using an internal electric field of a pn junction. The generated power is obtained by taking it out to the 114 side. Therefore, various improvements have been made so far in order to increase the amount of light incident on the semiconductor layer 112 even a little. For example, a first electrode layer 111, an amorphous silicon layer having a pin junction as the semiconductor layer 112, and a second electrode layer 114 are sequentially stacked over the light-transmitting substrate 101, and an effective wavelength is formed on the second electrode layer 114. The amount of light reaching the semiconductor layer 112 is increased by reflecting the incident light between the second electrode layer 114 and the first electrode layer 111 using an Ag electrode having a high reflectance in the region. Yes. This increases the reflectance of the second electrode layer 114, thereby effectively utilizing the long wavelength light transmitted through the semiconductor layer 112 and improving the short-circuit current. As described above, Ag is most commonly used as the second electrode layer 114 having a high reflectance.

JP 2008-85224 A

  As described above, in the solar cell module 170 in which the metal frame 165 is attached to the end portion of the solar cell module 170 with the resin 160 made of butyl rubber or the like, the incident light incident on the substrate 101 or the incident light is incident on the substrate 101 and the solar cell. When the scattered light generated by being scattered in the contact surface 110 and the solar cell 110 is incident on both ends of the solar cell module 170, most of the scattered light is absorbed by the resin 160. For this reason, incident light cannot be effectively contributed to power generation.

  The present invention has been made in view of the above situation, and provides a method for manufacturing a solar cell module in which light incident on the end of the solar cell module is incident again on the solar cell to increase the output current. With the goal.

  The method for manufacturing a solar cell module of the present invention includes a step of forming a first electrode layer on a first surface of a light-transmitting substrate, a step of forming a semiconductor layer on the first electrode layer, a semiconductor layer, and A step of forming a reflective conductive film on the second surface of the light-transmitting substrate by an in-line sputtering apparatus, and separating at least the first electrode layer or the reflective conductive film, one or more solar cells, and a second electrode And forming a first reflecting portion. Then, in the step of forming the reflective conductive film, the translucent substrate is transported by an in-line sputtering apparatus along the direction in which the current of the semiconductor layer flows.

  According to the present invention, it is possible to provide a solar cell module in which incident light is effectively contributed to power generation and output current is increased.

It is a top view of the solar cell module which concerns on embodiment of this invention. It is an expanded sectional view in the edge part of the solar cell module which concerns on embodiment shown in FIG. It is an expanded sectional view of the solar cell module edge part for explaining the manufacturing process of the solar cell module concerning the embodiment of the present invention. It is the schematic which shows the structure of the manufacturing apparatus of the solar cell module used for the manufacturing process of the solar cell module which concerns on embodiment of this invention. It is a top view of the conventional solar cell module. It is sectional drawing in the edge part of the solar cell module which concerns on the conventional embodiment.

Embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Therefore, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.
(Configuration of solar cell module)
The solar cell 70 manufactured with the manufacturing method of embodiment of this invention is demonstrated using drawing. As a top view of the solar cell module 70 manufactured in the embodiment of the present invention, a top view from the back surface side is shown in FIG. 1 (a), and a top view on the light receiving surface side is shown in FIG. 1 (b). FIG. 2 shows an enlarged cross-sectional view of the solar cell module 70 shown in FIG. FIG. 2 is an enlarged cross-sectional view corresponding to the AA cross section of the solar cell module 70 illustrated in FIG. 1.

  Hereinafter, the structure of the solar cell module 70 according to the embodiment will be described with reference to FIGS. 1 and 2. In FIG. 1, the sealing material 50 and the protective material 55 are omitted.

  The solar cell module 70 includes a substrate 1, a plurality of solar cells 10, an extraction electrode 20, an extraction wiring material 30, an output wiring material 35, an insulating film 40, a sealing material 50, and a protection material 55.

  The substrate 1 is a single substrate for forming a plurality of solar cells 10 and extraction electrodes 20. As the substrate 1, insulating glass, plastic, or the like can be used.

  The plurality of solar cells 10 are formed on the substrate 1 along the first direction. The plurality of solar cells 10 are arranged in parallel along a second direction substantially orthogonal to the first direction, and are electrically connected to each other in series.

  The solar cell 10 includes a first electrode layer 11, a semiconductor layer 12, a transparent conductive film 13, and a second electrode layer 14. The first electrode layer 11, the semiconductor layer 12, the transparent conductive film 13 and the second electrode layer 14 are sequentially stacked on the substrate 1 while being subjected to known laser patterning.

  The first electrode layer 11 is formed on the main surface of the substrate 1 and has conductivity and translucency. As the first electrode layer 11, in this embodiment, ZnO having high light transmittance, low resistance, and plasticity and low cost is used.

  The semiconductor layer 12 generates electric charges (electrons and holes) by incident light from the first electrode layer 11 side. As the semiconductor layer 12, for example, an amorphous silicon semiconductor layer having a pin junction or a pn junction as a basic structure or a single layer or a stacked body of a microcrystalline silicon semiconductor layer can be used. The semiconductor layer 12 of the present embodiment is composed of two photoelectric conversion units and is composed of an amorphous silicon semiconductor and a microcrystalline silicon semiconductor, respectively, from the first electrode layer 11 side. Note that in this specification, the term “microcrystal” means not only a complete crystal state but also a state partially including an amorphous state.

  The transparent conductive film 13 is formed on at least the semiconductor layer 12, and is formed so as to cover both the side end portion of the substrate 1 and the end portion on the light receiving surface side. The transparent conductive film 13 can prevent the semiconductor layer 12 and the second electrode layer 14 from being alloyed, and the connection resistance between the semiconductor layer 12 and the second electrode layer 14 can be reduced.

  The second electrode layer 14 is formed on the transparent conductive film 13. The transparent conductive film 13 and the second electrode layer 14 of one solar cell 10 are in contact with the first electrode layer 11 of another solar cell 10 adjacent to the one solar cell 10. Thereby, one solar cell 10 and the other solar cell 10 are electrically connected in series.

  Further, the second electrode layer 14 is formed so as to cover the side end portion and both end portions of the substrate 1, and constitutes a reflection portion 14 'composed of this portion. In the present embodiment, an Ag film having a high reflectivity with a thickness of 200 nm is used as the second electrode layer 14.

  The extraction electrode 20 extracts charges generated by the plurality of solar cells 10. The extraction electrode 20 includes a first electrode layer 11, a semiconductor layer 12, and a second electrode layer 14, similarly to the solar cell 10. The first electrode layer 11, the semiconductor layer 12, the second electrode layer 14, and the reflecting portion 14 ′ are sequentially stacked on the substrate 1 while performing known laser patterning. The extraction electrode 20 is formed on the substrate 1 along the first direction.

  The extraction wiring member 30 extracts electric charges from the extraction electrode 20. That is, the extraction wiring member 30 has a function as a collection electrode that collects charges from the extraction electrode 20.

  The lead-out wiring member 30 is composed of a conductive base material and solder plated on the outer periphery of the base material. The extraction wiring member 30 is soldered on the extraction electrode 20 along the extraction electrode 20 (along the first direction). As the substrate, copper or the like formed into a thin plate shape, a linear shape, or a twisted linear shape can be used. The extraction wiring member 30 may be partially soldered to the extraction electrode 20 at a plurality of locations.

  The output wiring member 35 guides the charges collected by the extraction wiring member 30 to the outside of the solar cell module 70. The output wiring member 35 has the same configuration as that of the extraction wiring member 30, and one end of the output wiring member 35 is soldered on the extraction wiring member 30. At this time, the insulating film 40 is disposed between the output wiring member 35 and the plurality of solar cells 10, and the output wiring member 35 and the plurality of solar cells 10 are insulated.

  The sealing material 50 seals the plurality of solar cells 10, the extraction electrodes 20, and the extraction wiring material 30 between the substrate 1 and the protective material 55, and is arranged so as to buffer the impact applied to the solar cells 10. Is done. In the present embodiment, EVA is used as the sealing material 50.

  The protective material 55 is disposed on the sealing material 50. In the present embodiment, a laminate made of PET / Al foil / PET is used as the protective material 55.

  One end of the output wiring member 35 that is not connected to the power extraction wiring 30 is drawn out from the openings provided in the sealing material 50 and the protective material 55 and connected to a terminal box (not shown).

  Then, the solar cell module 70 is completed by attaching an Al, SUS, or iron frame 65 to the end portions of the sealed solar cells 10 with an insulating and weather resistant resin 60 made of butyl rubber or the like. .

  In this embodiment, a photoelectric conversion unit in which an amorphous silicon semiconductor and a microcrystalline silicon semiconductor are sequentially stacked is used. However, a photoelectric conversion unit in which a single layer or three or more layers including a microcrystalline or amorphous layer are stacked is used. The same effect can be obtained even if is used.

Further, an intermediate layer made of ZnO, SnO ₂ , SiO ₂ , or MgZnO may be provided between the photoelectric conversion units so that the optical characteristics are improved.

The first electrode layer 11 is made of ZnO used in the present embodiment, SnO ₂ , In ₂ O ₃ , or one or more kinds of laminated bodies selected from metal oxides of TiO ₂ and Zn ₂ SnO _4. It may be configured. Note that these metal oxides may be doped with F, Sn, Al, Ga, Nb, or the like.

In this embodiment, after forming the transparent conductive film 13 made of ZnO, a single layer of Ag is formed as the second electrode layer 14. For example, the In ₂ O ₃ is sequentially formed on the semiconductor layer 12 as the transparent conductive film 13. , SnO ₂ , TiO ₂ , Zn ₂ SnO ₄ may be one or more layers, and the second electrode layer 14 may be a metal layer made of Al, Ti, Ni, or the like. Moreover, what is necessary is just to make it the structure which has at least 1 layer of the 2nd electrode layer 14, and it is good also as a structure without a transparent conductive film.

  As the sealing material 50, other than EVA, ethylene-based resin such as EEA, PVB, silicone, urethane, acrylic, epoxy resin may be used.

  As the protective material 55, in addition to a laminate made of PET / Al foil / PET, a single layer of a resin such as fluorine resin (ETFE, PVDF, PCTFE, etc.), PC, PET, PEN, PVF, acrylic, or metal foil A sandwiched structure, a steel plate such as SUS or Galvalume, or glass may be used.

  Here, the reflection part 14 ′, which is a characteristic part of the present embodiment, will be described in detail with reference to FIGS. 1 and 2.

  In the solar cell module 70 according to the present embodiment, the reflecting portion 14 ′ is formed so as to go around to the light receiving surface side when the second electrode layer 14 is formed on the back surface of the substrate 1, and the side edge portion and the edge portion of the substrate 1. Cover both sides. The reflecting portion 14 ′ that wraps around covers the invalid area that does not contribute to power generation on the light receiving surface and covers the solar cell 10 located at the end of the substrate 1. Thereby, the light incident on the substrate 1 can be effectively contributed to power generation without reducing the amount of light incident on the semiconductor layer 12 of the solar cell 10. That is, incident light directly incident on the end portion where the solar cell 10 and the extraction electrode 20 are not formed, the substrate 1 and the first electrode layer 11, the semiconductor layer 12 and the second electrode layer 14, or the first electrode layer 11 The light scattered at the interface of the semiconductor layer 12 and incident on the reflecting portion 14 ′ can be reflected again by the reflecting portion 14 ′ and incident on the semiconductor layer 12. The light reflected by the reflecting portion 14 ′ generates electron-hole pairs in the semiconductor layer 12 and generates a photocurrent by the internal electric field of the pn junction. That is, the reflecting portion 14 ′ contributes to increasing the short-circuit current of the solar cell module 70 by increasing the amount of light incident on the semiconductor layer 12. Between the reflection part 14 'which covers the side edge part of the board | substrate 1, and the board | substrate 1, it is good also as a structure which has the transparent conductive film 13, and can obtain the effect similar to the case where it does not have.

  A first separation groove 25 that separates the extraction electrode 20 and the reflection portion 14 ′ is formed on the back surface side of the solar cell module 70, and insulation at the end portion of the substrate 1 is ensured. In addition, in order to prevent the extraction electrode 20 and the plurality of solar cells 10 from being short-circuited via the reflection portion 14 ′, a second separation groove 26 is formed, and the extraction electrode 20 and the plurality of solar cells 10 are formed of the reflection portion 14 ′. Are separated from each other. Therefore, the plurality of solar cells 10 of the present embodiment can ensure insulation from the outside.

  Furthermore, the solar cell module 70 arrange | positions resin 60 so that reflection part 14 'formed may be covered, and the flame | frame 65 is attached. The resin 60 is disposed between the metal frame 65 and the solar cell module 70, and not only can be protected from an external impact applied to the solar cell module 70 as a cushioning material, but also by using the insulating resin 60. Insulation from the outside can be better secured.

  Further, at the end of the reflective portion 14 ′ located on the light receiving surface of the substrate 1, the transparent conductive film 13 covers the end of the reflective portion 14 ′ so that the end of the transparent conductive film 13 is not exposed. Good. Thereby, reflection part 14 'can prevent the penetration | invasion of the water | moisture content to the transparent conductive film 13, and can prevent that the light transmittance falls. Therefore, the light incident on the reflecting portion 14 ′ can be better reflected and incident on the solar cell 10.

As described above, according to the present invention, the light incident on the substrate 1 from the light receiving surface is reflected also at the end of the solar cell module 70 and is incident on the semiconductor layer 12 again, thereby reducing the amount of light incident on the semiconductor layer 12. In addition to increasing the short circuit current, the reliability of the solar cell module 70 can be improved.
(Method for manufacturing solar cell module)
Then, the manufacturing method of the solar cell module 70 which concerns on this embodiment is demonstrated with reference to FIG.1, FIG.2 and FIG.3. FIG. 3 is an enlarged cross-sectional view showing a manufacturing process at a portion corresponding to A′-A ′ of the solar cell module 70 shown in FIG.

First, as described in FIG. 3A, a first electrode layer 11 made of ZnO having a thickness of 600 nm is formed on a light-transmitting substrate 1 made of glass having a thickness of 4 mm by sputtering. And the YAG laser is irradiated from the 1st electrode layer 11 side of the translucent board | substrate 1, and the 1st electrode layer 11 is patterned in strip shape. For the laser separation processing, an Nd: YAG laser having a wavelength of about 1.06 μm, an energy density of 13 J / cm ³ and a pulse frequency of 3 kHz is used.

  Next, as described in FIG. 3B, the semiconductor layer 12 is formed by a plasma processing apparatus.

The semiconductor layer 12 is a p-type amorphous silicon semiconductor layer having a thickness of 10 nm using a mixed gas of SiH ₄ , CH ₄ , H ₂ and B ₂ H ₆ as a source gas, and a mixed gas of SiH ₄ and H _2. An i-type amorphous silicon semiconductor layer having a thickness of 300 nm is formed as a source gas, and an n-type amorphous silicon semiconductor layer having a thickness of 20 nm is formed using a mixed gas of SiH ₄ , H ₂ and PH ₄ as a source gas. Laminate. Subsequently, a p-type microcrystalline silicon semiconductor layer having a film thickness of 10 nm using a mixed gas of SiH ₄ , H ₂ and B ₂ H ₆ as a source gas, and a film thickness of 2000 nm using a mixed gas of SiH ₄ and H ₂ as a source gas. The i-type microcrystalline silicon semiconductor layer is formed by sequentially stacking an n-type microcrystalline silicon semiconductor layer having a thickness of 20 nm using a mixed gas of SiH ₄ , H ₂ and PH ₄ as a source gas. Details of various conditions of the plasma processing apparatus are shown in Table 1 below.

積層された半導体層１２、第１電極層１１のパターニング位置の横に第１電極層１１側からＹＡＧレーザを照射することにより基板１の裏面側に形成された半導体層１２を分離するように除去し、短冊状にパターニングする。当該レーザ分離加工には、エネルギー密度０．７Ｊ／ｃｍ^３、パルス周波数３ｋＨｚのＮｄ：ＹＡＧレーザを使用する。

By irradiating the YAG laser from the first electrode layer 11 side next to the patterning position of the stacked semiconductor layer 12 and the first electrode layer 11, the semiconductor layer 12 formed on the back surface side of the substrate 1 is removed so as to be separated. And patterning into strips. For the laser separation processing, an Nd: YAG laser having an energy density of 0.7 J / cm ³ and a pulse frequency of 3 kHz is used.

  Next, as shown in FIG. 3C, a transparent conductive film 13 made of ZnO is formed on the semiconductor layer 12 by sputtering. The transparent conductive film 13 is formed by the same method as that of the second electrode layer 14 so as to reach the region where the semiconductor layer 12 has been removed by patterning and the side edge and both ends of the substrate 1 to form a film. .

  Then, as described in FIG. 3D, an Ag film having a thickness of 200 nm is formed on the transparent conductive film 13 by sputtering to form the second electrode layer 14. As will be described later, the Ag film is formed so as to go around the region where the semiconductor layer 12 is removed by patterning and to the end of the light receiving surface including the end of the substrate 1. At this time, the edge part of the transparent conductive film 13 located in the light-receiving surface side is formed so that it may be covered with reflection film 14 '.

And as described in FIG.3 (e), the semiconductor layer 12, the transparent conductive film 13, and the 2nd electrode layer 14 are irradiated by irradiating the side part of the patterning position of the semiconductor layer 12 with a YAG laser from the back surface side. Separate and pattern into strips. For the laser separation processing, an Nd: YAG laser having an energy density of 0.7 J / cm ³ and a pulse frequency of 4 kHz is used.

As shown in FIG. 3 (f), the transparent conductive film 13 and the second electrode layer 14 wrap around the first separation groove 25 extending in the second direction for separation from the solar cell 10 and the extraction electrode 20. Are formed by a laser. Similarly, the second separation groove 26 extending in the first direction shown in FIG. 1 is formed by laser and separated from the extraction electrode 20. For the laser separation processing, an Nd: YAG laser having a wavelength of about 1.06 μm, an energy density of 13 J / cm ³ and a pulse frequency of 3 kHz is used. The first separation groove 25 and the second separation groove 26 may have a width of 1 mm or more in order to effectively insulate.

  As described above, the plurality of solar cells 10, the extraction electrode 20, and the reflection portion 14 ′ connected in series to each other are formed on the substrate 1.

  As shown in FIG. 3G, an extraction wiring member 30 is disposed on the extraction electrode 20 and soldered.

  Then, as described in FIG. 3 (h), after the insulating film 40 is disposed on the plurality of solar cells 10, the output wiring member 35 is disposed on the insulating film 40, and one end portion of the output wiring member 35. Is connected to the extraction wiring member 30.

  As shown in FIG. 2, a sealing material 50 made of EVA and a protective material 55 made of PET / Al foil / PET are provided on the second electrode layer 14 and the extraction wiring material 30 of the solar cell 10. At this time, one end of the output wiring member 35 that is not connected to the power extraction wiring 30 is drawn out from the openings provided in the sealing member 50 and the protective member 55 to be formed. Then, a terminal box (not shown) is connected to the end portion of the output wiring member 35 drawn from the opening.

  As shown in FIG. 2, a buffer material made of resin 60 made of butyl rubber or the like is provided at the end of the sealed plurality of solar cells 10, and a frame 65 made of Al is provided to complete the solar cell module 70. .

  Below, the sputtering method of the 2nd electrode layer 14 which is the characteristics of this invention is explained in full detail with reference to FIG. FIG. 4 is a schematic diagram of an in-line sputtering apparatus 80 that sequentially conveys a plurality of substrates and sequentially performs sputtering. 4A is a schematic view showing the structure of the in-line sputtering apparatus 80, and FIG. 4B is a top view showing how the substrate 1 is transported inside the reaction chamber 81. As shown in FIG. In FIG. 4B, a target 82 made of Ag, a support portion 83 that supports the target 82, an electrode 85 provided under the substrate 1, and a roller 86 that conveys the substrate 1 are omitted.

The second electrode layer 14 is formed by the in-line sputtering apparatus 80 illustrated in FIG. In this embodiment, first, a transparent substrate 1 is prepared in which a first electrode layer 11 and a semiconductor layer 12 are sequentially stacked. Then, in the reaction chamber 81 of the in-line sputtering apparatus 80 shown in FIG. 4A, the substrate 1 formed up to the semiconductor layer 12 is heated to 60 ° C. to 120 ° C. when the second electrode layer 14 is formed, and conveyed. To do. The reaction chamber 81 is evacuated to about 1.0 × 10 ⁻⁵ Pa by the vacuum pump 90, and then introduced with argon gas (hereinafter simply referred to as Ar) and oxygen (hereinafter simply referred to as O ₂ ) through the intake port 82, and the internal pressure is increased. Is maintained at 0.4 to 0.7 Pa. A target 82 made of Ag is fixed on a support portion 83, and a positive electrode of a power supply device 95 is connected to the support portion 83, and a negative electrode of the power supply device is connected to an electrode 85 provided on the bottom plate 84 and the substrate 1. Then, the substrate 1 is moved while discharging at a DC power density of 0.9 to 4.0 W / cm ² , the target 83 is sputtered, and the second electrode layer 14 made of Ag is continuously formed on the semiconductor layer 12. Formed.

  In the present embodiment, an adhesion preventing plate 84 is disposed between the target 82 and the substrate 1, and an Ag film is formed on the substrate 1 through the opening of the adhesion preventing plate 84. The opening of the deposition preventing plate 84 is provided with a larger opening than the length of the substrate 1 in a direction substantially orthogonal to the substrate transport direction so that the film formation species can more easily enter both ends of the substrate 1 in the first direction. Is formed.

  Further, in the solar cell module 70 shown in FIG. 1A, photocurrent can be generated by making light incident on the semiconductor layer 12 of the solar cell 10, while light can be made incident on the extraction electrode 20. Cannot contribute to power generation. For this reason, when forming reflection part 14 'in an edge part, the edge part of the several solar cell 10 formed in the board | substrate 1 compared with the side extended in the 1st direction where the extraction electrode 20 of the board | substrate 1 adjoins. More favorable light can be made to contribute to power generation by forming a good reflecting portion 14 'on the side extending in the adjacent second direction.

  Moreover, even when the favorable reflection part 14 'is formed on the side extending in the second direction where the ends of the plurality of solar cells 10 formed on the substrate 1 are adjacent to each other, the output of the solar cell module 70 is , The reflecting portion 14 ′ is incident on the semiconductor layer 12, and the solar cell 10 having the smallest current amount among the current amounts generated by the solar cell 10 is bound. For this reason, it is desirable that the reflecting portion 14 ′ formed on the side extending in the second direction where the end portions of the plurality of solar cells 10 are adjacent is uniform.

  In the in-line sputtering apparatus 80, the substrate 1 forms an Ag film on the substrate 1 while being conveyed by the roller 86. For this reason, when comparing a side substantially parallel to the direction in which the substrate 1 is transported and a side substantially orthogonal to the substrate transport direction, the reflecting portion 14 ′ in which the Ag film uniformly wraps around the side substantially parallel to the transport direction. In contrast, the Ag film hardly wraps around the side substantially perpendicular to the transport direction, and it is difficult to control the reflective portion 14 'to a suitable film thickness.

  For this reason, in this embodiment, in order to form the reflecting portion 14 ′ which is a suitable condition on the side extending in the second direction in which the end portions of the plurality of solar cells 10 are adjacent, the transport direction of the substrate 1 and the substrate The Ag film was formed so that the second direction in which the ends of the plurality of solar cells 10 formed in 1 are adjacent to each other is substantially the same direction. That is, the reflective part of uniform thickness can be formed by conveying a board | substrate in the substantially the same direction as the edge | side extended in the 2nd direction where the edge part of the several solar cell 10 adjoins. Further, by providing the reflecting portion 14 ′ on the side extending in the second direction where the end portions of the plurality of solar cells 10 are adjacent to each other, the light can be reflected better and more light can be incident on the solar cell 10. Can do. Thereby, the photocurrent generated in each individual solar cell 10 can be increased, and a larger output can be obtained as the solar cell module 70.

It should be noted that, similarly to the present embodiment, in the case where ZnO is formed as the transparent conductive film 13 and Ag single layer is formed as the second electrode layer 14, similarly, In _{2 is} used instead of ZnO and Ag used this time as the target 82. A transparent conductive film 13 and a second electrode layer 14 can be formed by setting and sputtering a metal oxide such as O ₃ , SnO ₂ , TiO ₂ , Zn ₂ SnO _4, or a metal such as Al, Ti, or Ni. it can. Moreover, the transparent conductive film 13 and the second electrode layer 14 having a plurality of layers can be formed by using a plurality of similar apparatuses or by repeatedly sputtering the target 83.

  Further, in this embodiment, a direct current (DC) sputtering apparatus is used as the inline sputtering apparatus 80, but high frequency sputtering, magnetron sputtering, or the like can be applied.

  Further, the transparent conductive film 13 and the second electrode layer 14 that have wrapped around are the solar cell 10 and the extraction electrode that are configured by laminating the first electrode layer 11, the semiconductor layer 12, the transparent conductive film 13, and the second electrode layer 14. In order to separate from 20, a 1 mm first separation groove 25 extending in the second direction is formed by laser. Similarly, a 1 mm second separation groove 26 extending in the first direction shown in FIG. 1 is formed by laser and separated from the extraction electrode 20. Thereby, when the solar cell 10 is sealed with the protective material 55 via the sealing material 50, the solar cell 10 is ensured to be insulated from the outside and can be improved in reliability.

  As described above, according to the method for manufacturing a solar cell module of the present invention, the light incident on the substrate 1 from the light receiving surface is reflected by the reflecting portion 14 ′ and incident again on the semiconductor layer 12 to increase the short-circuit current. In addition, since the insulation between the solar cell module 90 and the outside can be ensured, the reliability can be improved. That is, in the method for manufacturing a solar cell according to the present invention, it is possible to achieve both improvement in output of the solar cell module and prevention of reduction in reliability of the solar cell.

DESCRIPTION OF SYMBOLS 1 ... Substrate 10 ... Solar cell 11 ... 1st electrode layer 12 ... Semiconductor layer 13 ... Transparent conductive film 14 ... 2nd electrode layer 14 '... Reflecting part 20 ... Extraction electrode 25 ... 1st separation groove 26 ... 2nd separation groove 30 ... Extraction wiring material 35 ... Output wiring material 40 ... Insulating film 50 ... Sealing material 55 ... Protection material 70 ... Solar cell module 80 ... In-line sputtering device

Claims (5)

Forming a first electrode layer on the first surface of the translucent substrate;
Forming a semiconductor layer on the first electrode layer;
Forming a reflective conductive film on the semiconductor layer and on the second surface of the translucent substrate by an in-line sputtering device;
Separating at least the first electrode layer or the reflective conductive film to form one or a plurality of solar cells, and a second electrode and a first reflective portion;
With
In the step of forming the reflective conductive film, the translucent substrate is transported by the in-line sputtering apparatus along the direction in which the current of the semiconductor layer flows. Forming a first electrode layer on the first surface of the translucent substrate;
Forming a semiconductor layer on the first electrode layer;
Forming a reflective conductive film on the semiconductor layer and on a side end surface of the translucent substrate by an in-line sputtering device;
Separating at least the first electrode layer or the reflective conductive film to form one or a plurality of solar cells, and a second electrode and a second reflective portion;
With
In the step of forming the reflective conductive film, the translucent substrate is transported by the in-line sputtering apparatus along the direction in which the current of the semiconductor layer flows. Forming a first electrode layer on the first surface of the translucent substrate;
Forming a semiconductor layer on the first electrode layer;
Forming a reflective conductive film on the semiconductor layer and on the second and side end surfaces of the translucent substrate by an in-line sputtering apparatus;
Separating at least the first electrode layer or the reflective conductive film and forming one or a plurality of solar cells, a second electrode, a first reflective portion and a second reflective portion;
With
In the step of forming the reflective conductive film, the translucent substrate is transported by the in-line sputtering apparatus along the direction in which the current of the semiconductor layer flows.   4. The method for manufacturing a solar cell module according to claim 1, wherein a light-transmitting conductive film exists between the first reflecting portion and the light-transmitting substrate. 5. 5. The method of manufacturing a solar cell module according to claim 4, wherein the first reflective portion covers an end portion of the translucent conductive film on the second surface of the translucent substrate.

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