JP2012039038A - Thin film solar cell and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin film solar cell in which the output of the thin film solar cell is increased by increasing an effective area of a transparent electrode layer and insulation quality in a second through hole is secured to reduce the percent defective in the manufacturing of the thin film solar cell, and to provide a method for manufacturing the thin film solar cell.SOLUTION: In a thin film solar cell 1 of this invention, insulative tape 11 is placed between a first back electrode layer and a second back electrode layer to cover a second through hole 8. On the insulative tape 11, a photoelectric conversion layer 4 and a transparent electrode layer 5 are laminated from a side of one surface 2a of an insulative substrate 2, and the second back electrode layer 6 is laminated from a side of the other surface 2b of the insulative substrate 2. The transparent electrode layer 5 and the second back electrode layer 6 are electrically insulated by an insulative resin 11 in the second through hole 8.

Description

  The present invention relates to a thin film solar cell in which a metal electrode layer, a photoelectric conversion layer, and a transparent electrode layer are laminated on an insulating substrate, and a method for manufacturing the same.

FIG. 8 is a plan view of a conventional thin film solar cell. 9 is a cross-sectional view taken along the line AA in FIG. 8, and FIG. 10 is a cross-sectional view taken along the line BB in FIG.
As shown in FIGS. 9 and 10, the conventional thin-film solar cell 21 includes an insulating substrate 22. Metal electrode layers 23 are formed on both surfaces 22 a and 22 b of the insulating substrate 22. Here, the metal electrode layer 23 on one surface 22a of the insulating substrate 22 functions as the back electrode layer 23a, and the metal electrode layer 23 on the other surface 22b of the insulating substrate 22 is the first back electrode. It functions as the layer 23b.

  Further, as shown in FIGS. 9 and 10, the photoelectric conversion layer 24 and the transparent electrode layer 25 are laminated in this order on the back electrode layer 23a. On the other hand, the second back electrode layer 26 is laminated on the first back electrode layer 23b.

  As shown in FIGS. 9 and 10, the insulating substrate 22 is provided with a first through hole 27 that penetrates the insulating substrate 22, so that the transparent electrode layer 24 and the second back electrode layer 26 are provided. The first through hole 27 is electrically connected. Further, as shown in FIGS. 9 and 11, the insulating substrate 22 is provided with a second through hole 28 that penetrates the insulating substrate 22, and a back electrode layer 23a and a first back electrode layer 23b are provided. The second through hole 28 is electrically connected.

  As shown in FIG. 8, the layer stacked on one surface 22a of the insulating substrate 22 is divided by the first patterning line 29, and the layer stacked on the other surface 22b of the insulating substrate 22 is It is divided by two patterning lines 30. Thereby, the laminated layer on the insulating substrate 22 is divided into a plurality of unit cells.

  Here, the first patterning lines 29 and the second patterning lines 30 are alternately arranged on the insulating substrate 22. By separating the electrode layers on both surfaces 22a and 22b of the insulating substrate 22 from each other and connecting the electrode layers on both surfaces 22a and 22b of the insulating substrate 22 with the second through-holes 28, adjacent unit cells It has a structure connected in series.

  On the other hand, Patent Document 1 discloses another example of a conventional thin film solar cell. In the thin film solar cell of Patent Document 1, a first electrode layer, a photoelectric conversion layer, and a second electrode layer are laminated on one surface of a film substrate made of an electrically insulating resin, opposite to the film substrate. A third electrode layer and a fourth electrode layer are stacked on the side (back surface).

  Patent Document 2 discloses still another example of a conventional thin film solar cell. In the thin film solar cell of Patent Document 2, the connection hole is closed with a printed electrode made of a conductive material (particularly, see paragraph 0035 and FIG. 27).

JP 2001-298203 A JP-A-6-342924

However, the following problems occur in the configuration shown in FIGS.
In the conventional configuration, when the transparent electrode layer 26 is formed so that the transparent electrode layer 25 and the second back electrode layer 26 are not in contact with each other in the second through hole 28, the vicinity of the second through hole 28 is formed. Had been masked. Therefore, as shown in FIG. 10B, the transparent electrode layer 25 is not formed in the vicinity of the second through-hole 28. Therefore, in the conventional configuration, the effective area of the transparent electrode layer 25 is limited. Since the second through holes 28 are arranged at a predetermined interval in consideration of the electric resistance of the first and second back electrode layers 23b and 26, the transparent electrode layer 25 cannot be formed on the insulating substrate 22. Regions are provided at regular intervals. Therefore, there is a problem that the effective area of the transparent electrode layer 25 is reduced, and the output of the thin film solar cell 21 is also reduced in proportion thereto.

  Further, since the vicinity of the second through hole 28 is masked, the transparent electrode layer 25 on the insulating substrate 22 and the like can be damaged when the transparent electrode layer 25 on the insulating substrate 22 and the mask come into contact with each other. There was sex. Thus, when the layer on the insulating substrate 22 is damaged, the leakage current and the like increase, and there is a problem that the defect rate when manufacturing the thin-film solar cell 21 increases.

  Moreover, in the technique disclosed in Patent Document 2, since the connection hole is closed with a conductive material, there is a problem in that the insulation in the connection hole is not sufficient and the leakage current increases.

  The present invention has been made in view of such a situation, and its purpose is to increase the effective area of the transparent electrode layer by simple means to increase the output of the thin film solar cell, and to increase the output of the second through hole. An object of the present invention is to provide a thin film solar cell capable of reducing the defect rate when manufacturing a thin film solar cell while ensuring insulation, and a method for manufacturing the same.

    According to the thin film solar cell according to the present invention, the back electrode layer, the photoelectric conversion layer, and the transparent electrode layer are laminated in this order on one surface of the insulating substrate, and the other surface of the insulating substrate is stacked on the other surface. The first back electrode layer and the second back electrode layer are stacked in this order, and a plurality of the insulating substrates are formed by alternately forming patterning lines on the layers stacked on both surfaces of the insulating substrate. The transparent electrode layer and the second back electrode layer are electrically connected via a first through hole penetrating the insulating substrate, and the back electrode layer and the second back electrode layer are electrically connected to each other. In the thin film solar cell in which one back electrode layer is electrically connected via a second through hole penetrating the insulating substrate and adjacent unit cells are connected in series, the second through hole An insulating tape for sealing the first back electrode layer Affixed between the second back electrode layer, and the transparent electrode layer and the second back electrode layer is assumed to be electrically insulated by the insulating tape in the second through hole.

Moreover, according to the thin film solar cell of this invention, it is preferable in the said insulating tape being a polyimide type heat resistant adhesive tape.
Moreover, according to the thin film solar cell of this invention, the said insulating substrate is formed from the film material.

Moreover, according to the thin film solar cell of this invention, the said film material is a heat resistant film of a polyimide or a polyimide amide.
Moreover, according to the thin film solar cell of this invention, the said photoelectric converting layer is either an amorphous semiconductor or an amorphous compound semiconductor, a dye-sensitized solar cell, and an organic solar cell.

  In order to solve the above-described problems of the prior art, a method of manufacturing a thin film solar cell according to the present invention includes a step of forming a second through hole in an insulating substrate, and a back electrode layer on one surface of the insulating substrate. And forming a first back electrode layer on the other surface of the insulating substrate, and forming the back electrode layer and the first back electrode layer, and then forming a first back electrode layer on the insulating substrate. Forming a through hole, a step of applying an insulating tape for closing the second through hole between the first back electrode layer and the second back electrode layer, and one of the insulating substrates Laminating the photoelectric conversion layer and the transparent electrode layer in this order from the surface side of the substrate, laminating the second back electrode layer from the other surface side of the insulating substrate, and laminating the both surfaces of the insulating substrate Patterning lines alternately on the layer Form and is intended to include dividing the insulating substrate into a plurality of unit cells.

  In addition, according to the method for manufacturing a thin film solar cell of the present invention, after the insulating tape for closing the second through hole is pasted on the first back electrode layer side, and one of the insulating substrates Before laminating the photoelectric conversion layer from the surface side, the insulating tape is degassed by heating. Further, when the insulating tape is thermosetting polyimide, curing (curing) is performed.

Moreover, according to the manufacturing method of the thin film solar cell of this invention, it is preferable that the said insulating tape is a polyimide-type heat resistant adhesive tape.
Moreover, according to the manufacturing method of the thin film solar cell of this invention, the said insulating substrate is formed from the film material.

Moreover, according to the manufacturing method of the thin film solar cell of this invention, the said film material is a heat resistant film of a polyimide or a polyimide amide.
According to the method for manufacturing a thin film solar cell of the present invention, the step of applying an insulating tape for closing the second through hole between the first back electrode layer and the second back electrode layer includes In a state where the film material is partially wound around an unwinding roll or a transporting roll, an insulating tape for closing the second through hole is interposed between the first back electrode layer and the second back electrode layer. After the second through-hole is covered and pasted, the insulating tape is degassed by heating, and when the insulating tape is thermosetting polyimide, the insulating tape is cured (cured).

  According to the thin film solar cell according to the present invention, the back electrode layer, the photoelectric conversion layer, and the transparent electrode layer are laminated in this order on one surface of the insulating substrate, and the other surface of the insulating substrate is stacked on the other surface. The first back electrode layer and the second back electrode layer are stacked in this order, and a plurality of the insulating substrates are formed by alternately forming patterning lines on the layers stacked on both surfaces of the insulating substrate. The transparent electrode layer and the second back electrode layer are electrically connected via a first through hole penetrating the insulating substrate, and the back electrode layer and the second back electrode layer are electrically connected to each other. In the thin film solar cell in which one back electrode layer is electrically connected via a second through hole penetrating the insulating substrate and adjacent unit cells are connected in series, the second through hole An insulating tape for sealing the first back electrode layer The insulating resin is laminated with the photoelectric conversion layer and the transparent electrode layer from the one surface side of the insulating substrate, and from the other surface side of the insulating substrate. Since the second back electrode layer is laminated and the transparent electrode layer and the second back electrode layer are electrically insulated by the insulating tape in the second through-hole, The transparent electrode layer is also laminated in the vicinity of the hole, and the effective area of the transparent electrode layer can be expanded to increase the output of the thin film solar cell. And since an insulating tape is arrange | positioned between a transparent electrode and a 2nd back electrode in a 2nd through-hole, the insulation in a 2nd through-hole can also be ensured.

  Moreover, according to the thin film solar cell according to the present invention, by using a polyimide heat-resistant adhesive tape as the insulating tape, it can be used in a high-temperature process when forming the photoelectric conversion layer, the transparent electrode layer, and the second back electrode layer. Can be used.

  The pressure-sensitive adhesive tape requires heat resistance higher than the temperature heated in the photoelectric conversion layer and transparent electrode layer forming step and the degassing step. Specifically, the heat resistance is 250 ° C. or higher, preferably 300 ° C. or higher. The one with is good.

Moreover, according to the thin film solar cell which concerns on this invention, since insulation of a transparent electrode layer and a 2nd back electrode layer is performed by sticking an insulating tape, it can implement | achieve with a simple means in a short time.
Further, according to the thin film solar cell of the present invention, since the insulating substrate is formed of a film material, the insulating substrate is transported by a transport roll (for example, roll-to-roll). The thin film solar cell can be efficiently manufactured. At this time, in order to reduce the roll diameter when the film substrate is wound, the thickness of the adhesive tape for closing the through hole is preferably about 0.1 mm or less.

  According to the method for manufacturing a thin film solar cell of the present invention, the step of forming the second through hole in the insulating substrate, the formation of the back electrode layer on one surface of the insulating substrate, and the insulating property Forming a first back electrode layer on the other surface of the substrate; forming a first through hole in the insulating substrate after forming the back electrode layer and the first back electrode layer; A step of disposing an insulating resin inside the second through hole; and after disposing the insulating resin inside the second through hole, a photoelectric conversion layer from one surface side of the insulating substrate; The transparent electrode layers are laminated in this order, and the second back electrode layer is laminated from the other surface side of the insulating substrate, and the layers laminated on both surfaces of the insulating substrate are alternately patterned. Forming the line, said insulating substrate Because it includes a step of dividing into a plurality of unit cells, as in the prior art it eliminates the need for a masking process in the vicinity of the second through-hole, thereby improving the yield in the manufacture of thin film solar cells. In addition, since it is not necessary to perform mask processing in the vicinity of the second through hole, the mask and the layer on the substrate do not come into contact with each other and the layer on the substrate is not damaged. Thereby, leak current does not increase in the thin film solar cell, and the defect rate when manufacturing the thin film solar cell can be reduced.

  Further, since the transparent electrode layer is also laminated in the vicinity of the second through-hole, the effective area of the transparent electrode layer can be expanded and the output of the thin film solar cell can be increased. In addition, since the insulating tape is disposed between the transparent electrode layer and the second back electrode layer in the second through hole, the insulating property in the second through hole can be ensured.

  Further, according to the method for manufacturing a thin-film solar cell according to the present invention, the step of disposing an insulating tape between the first back electrode layer and the second back electrode layer in order to close the second through hole, In a state where the film material is partially wound around an unwinding roll or a transporting roll, an insulating tape is applied to the first back electrode side in order to close the second through hole, and then the insulating tape is attached. Since it is a step of degassing by heating, the film material is held by the roll to be in a stable state, and the insulating tape can be arranged more easily.

It is a top view of the thin film solar cell concerning a 1st embodiment of the present invention. (A) is the sectional view on the AA line of FIG. 1, (b) is an enlarged view of C in (a). (A) is the BB sectional drawing of FIG. 1, (b) is an enlarged view of D in (a). It is a top view of the thin film solar cell which concerns on 2nd Embodiment of this invention. (A) is the sectional view on the AA line of FIG. 4, (b) is an enlarged view of C in (a). (A) is the BB sectional drawing of FIG. 4, (b) is an enlarged view of D in (a). It is a flowchart at the time of manufacturing the thin film solar cell which concerns on embodiment of this invention. It is a top view of the conventional thin film solar cell. (A) is the sectional view on the AA line of FIG. 8, (b) is an enlarged view of C in (a). (A) is the BB sectional drawing of FIG. 8, (b) is an enlarged view of D in (a). It is a figure regarding the manufacturing method of this invention. (a) is a figure which shows a processing flow, (b) is a figure which shows the whole structure.

Hereinafter, a thin film solar cell according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of the thin-film solar cell according to the first embodiment. 2 is a cross-sectional view taken along the line AA in FIG. 1, and (b) is an enlarged view of C in (a). 3 is a cross-sectional view taken along line BB in FIG. 1, and (b) is an enlarged view of D in (a).
[First Embodiment]
As shown in FIGS. 1 and 2, the thin-film solar cell 1 according to this embodiment includes an insulating substrate 2. The insulating substrate 2 is made of a film material, for example, a material such as polyimide, polyimide amide, or aluminide.

  As shown in FIG. 2, a metal electrode layer 3 made of a metal such as Ag / ZnO is formed on both surfaces 2a and 2b of the insulating substrate 2. Here, the metal electrode layer 3 on the one surface 2a of the insulating substrate 2 functions as the back electrode layer 3a, and the metal electrode layer 3 on the other surface 2b of the insulating substrate 2 is the first back electrode. It functions as the layer 3b.

  As shown in FIG. 2, the photoelectric conversion layer 4 and the transparent electrode layer 5 are laminated in this order on the back electrode layer 3 a on the one surface 2 a of the insulating substrate 2. Here, as the photoelectric conversion layer 4, an amorphous semiconductor, an amorphous compound semiconductor, a dye-sensitized solar cell, or an organic solar cell can be used. On the other hand, the second back electrode layer 6 is laminated on the first back electrode layer 3 b on the other surface 2 b of the insulating substrate 2.

  As shown in FIG. 1, the layers (back electrode layer 3a, photoelectric conversion layer 4, transparent electrode layer 5) laminated on one surface 2a of the insulating substrate 2 are formed by a first patterning line 9 by laser processing. It is divided into multiple parts.

  Further, as shown in FIGS. 1 and 3, the layers (first back electrode layer 3b and second back electrode layer 6) laminated on the other surface 2b of the insulating substrate 2 are similarly laser processed. The second patterning line 10 is divided into a plurality of parts. Here, the first patterning lines 9 and the second patterning lines 10 are alternately arranged on the insulating substrate 2.

  As shown in FIGS. 1 and 2, the insulating substrate 2 is provided with a first through hole 7 that penetrates the insulating substrate 2. The transparent electrode layer 5 and the second back electrode layer 6 are connected so as to overlap each other on the side wall portion 7 a of the first through hole 7. Thereby, the unit cell (unit solar cell) which consists of each layer on the one surface 2a of the insulating substrate 2 and each layer on the other surface 2b is formed.

  As shown in FIGS. 1 and 3, the insulating substrate 2 is provided with a second through hole 8 that penetrates the insulating substrate 2. The back electrode layer 3 a and the first back electrode layer 3 b are electrically connected via the side wall 8 a of the second through hole 8. That is, adjacent unit cells are electrically connected by the second through hole 8. Specifically, the first and second through holes 7 and 8 are formed by the first and second back electrode layers 3b and 6 → the first through hole 7 → the transparent electrode layer 5 → the photoelectric conversion layer 4 → the back electrode layer. It is used for connecting in the order of 3a → second through hole 8 → first back electrode layer 3b.

As described above, the thin film solar cell 1 is configured by electrically connecting adjacent unit cells in series.
As a feature of the present embodiment, as shown in FIG. 3, an insulating tape 11 is disposed on the opposite side of the first back electrode to close the second through hole 8. The photoelectric conversion layer 4 and the transparent electrode layer 5 are laminated on one surface 11 a of the insulating tape 11. The second back electrode layer 6 is laminated on the other surface 11 b of the insulating tape 11.

From the above configuration, the transparent electrode layer 5 and the second back electrode layer 6 are electrically insulated by the insulating tape 11 in the second through hole 8.
In addition, in order to block the 2nd through-hole 8, the heat resistant adhesive tape of a polyimide can be used as the insulating tape 11 arrange | positioned between a 1st back electrode layer and a 2nd back electrode layer. The heat resistant temperature is preferably 250 degrees or more. For example, high heat-resistant adhesives such as polyimide tapes (5413, etc.) from Sumitomo 3M Limited, and high-heat-resistant silicone adhesives and adhesive tapes made of insulating polyimides with high heat resistance An adhesive tape made of a highly heat-resistant sheet can be used. The adhesive material may be acrylic such as 7414 of Sumitomo 3M Limited. Further, a polyimide sheet coated with a thermosetting polyimide or a polyimide sheet combined with a thermoplastic polyimide (for example, LARC-TPI from Sumitomo Chemical) may be used.

Next, the manufacturing method of the thin film solar cell which concerns on embodiment of this invention is demonstrated with reference to drawings. FIG. 7 is a flowchart for manufacturing the thin-film solar cell 1 according to this embodiment.
The thin film solar cell 1 according to this embodiment uses the film material as described above as the insulating substrate 2. As a method for manufacturing the thin-film solar cell 1, a roll-to-roll method or an ink jet printing technique is used. For example, the roll-to-roll method is a method in which a film material substrate is conveyed by a plurality of rolls (conveying means), and a thin film is continuously formed on the substrate in a film forming chamber that is continuously arranged.

  When the thin-film solar cell 1 is manufactured, as shown in FIG. 7, first, in step S1, the insulating substrate 2 is pretreated. Specifically, pretreatment such as cleaning the surface by exposing the insulating substrate 2 to plasma is performed.

  Next, in step S <b> 2, the second through hole 8 is formed in the insulating substrate 2. The second through hole 8 is formed by punching (a perforating method). The shape of the second through hole 8 is a circle having a diameter of 1 mm. The second through hole 8 has a circular diameter in the range of 0.05-1 mm. The number of perforations in the second through hole 8 can be adjusted according to the design.

  Next, in step S3, a back electrode layer 3a and a first back electrode layer 3b are formed on both surfaces 2a and 2b of the insulating substrate 2 by performing a sputtering process. At this time, the back electrode layer 3 a and the first back electrode layer 3 b are electrically connected through the second through hole 8.

  Thereafter, in step S4, the layers formed on both surfaces 2a and 2b of the insulating substrate 2 are linearly removed by laser processing to form a primary pattern line (not shown). At this time, the lines formed on both surfaces 2a and 2b of the insulating substrate 2 are formed so as to be shifted from each other.

In step S <b> 5, the first through hole 7 is formed in the insulating substrate 2. The first through hole 7 is formed by punching.
Next, in step S <b> 6, an insulating tape 11 is applied between the first back electrode and the second back electrode layer in order to close the second through hole 8. As a method of sticking the insulating tape 11 on the first back electrode side in order to block the second through-hole 8, the film substrate 2 is partially wound around the unwinding roll or the transporting roll. At the position where the second through-hole 8 is conveyed and wound around the unwinding roll or the conveyance roll, the insulating tape 11 is placed on the side opposite to the first back electrode of the film substrate so as to close the second through-hole 8. There is a method of pressing and sticking to a roll.

The details of the process are as follows.
First, FIG. 11A shows the process flow, and FIG. 11B shows the entire apparatus.
At the position where the substrate 2 is unwound from the substrate unwinding portion 21 and the through hole 8 is wound around the roll of the substrate unwinding portion 21, the insulating tape is pushed out from the insulating tape unwinding portion 23, and the first back surface of the film substrate 2 Affix from the opposite side of the electrode. Thereafter, the insulating tape 11 is degassed by heating in the heat treatment section 25. Further, when the insulating tape 11 is thermosetting polyimide, curing is performed, and the substrate 2 is taken up by the substrate winding section 22. Take up around. Although not shown in the drawings, the first tape of the insulating tape 11 from the opposite side of the first back electrode of the film substrate 2 is attached to the transport roll 26 disposed between the substrate unwinding portion 21 and the heat treatment portion 25. You may carry out in the part of.

  In the insulating tape attaching part 24, when the insulating tape 11 is pushed out and attached so as to close the through hole 8 at the position where the through hole 8 is in the insulating tape attaching part 24, the insulating tape 11 is cut. To separate from the film substrate 2. When the film substrate 2 is transported and the next through-hole 8 comes to the insulating tape attaching part 24, the attaching of the insulating tape 11 is repeated. This procedure is the same when the insulating tape attaching part 24 faces the substrate unwinding part 21 and when it faces the transport roll 26.

  Next, in step S7, the insulating substrate 2 on which the back electrode layer 3a and the first back electrode layer 3b and the insulating tape 11 are formed is degassed in a heating furnace or the like. Cure for thermosetting polyimide.

  In step S8, the photoelectric conversion layer 4 is formed on the back electrode layer 3a of the insulating substrate 2, and then in step S9, the transparent electrode layer 5 is further formed on the photoelectric conversion layer 4. At this time, as shown in FIG. 3B, the photoelectric conversion layer 4 and the transparent electrode layer 5 are also laminated on one surface 11 a of the insulating tape 11.

  Next, in step S <b> 10, the second back electrode layer 6 is formed on the first back electrode layer 3 b of the insulating substrate 2. At this time, as shown in FIG. 3B, the second back electrode layer 6 is laminated on the other surface 11 b of the insulating tape 11.

  Next, in step S11, the photoelectric conversion layer 4 and the transparent electrode layer 5 on the primary patterning line formed in step S4 are removed again linearly by laser processing to form a first patterning line 9.

  Further, in step S12, the second back electrode layer 6 on the primary patterning line formed in step S4 is again removed by laser processing to form a second patterning line 10 again. The layers on the insulating substrate 2 are separated into a plurality of unit cells by the first and second patterning lines 9 and 10, and the series connection of the thin film solar cells 1 is completed.

  According to the thin-film solar cell 1 according to the first embodiment of the present invention, the back electrode layer 3a, the photoelectric conversion layer 4, and the transparent electrode layer 5 are laminated in this order on one surface 2a of the insulating substrate 2. The first back electrode layer 3b and the second back electrode layer 6 are laminated in this order on the other surface 2b of the insulating substrate 2, and the layers laminated on both surfaces 2a and 2b of the insulating substrate 2 On the other hand, by alternately forming the first and second patterning lines 9 and 10, the insulating substrate 2 is divided into a plurality of unit cells, and the transparent electrode layer 5 and the second back electrode layer 6 are insulated. The first and second back electrode layers 3a and 3b are electrically connected via a first through hole 7 penetrating the substrate 2, and the second through hole 8 penetrating the insulating substrate 2 is connected to the back electrode layer 3a and the first back electrode layer 3b. The thin film solar cell 1 is electrically connected to each other and adjacent unit cells are connected in series. In order to close the second through-hole 8, an insulating tape 11 is disposed on the first back electrode side, and the insulating tape 11 is transparent to the photoelectric conversion layer 4 from the one surface 2 a side of the insulating substrate 2. The electrode layer 5 is laminated, the second back electrode layer 6 is laminated from the other surface 2b side of the insulating substrate 2, and the transparent electrode layer 5 and the second back electrode layer 6 are Since the through hole 8 is electrically insulated by the insulating tape 11, the transparent electrode layer 5 is also laminated in the vicinity of the second through hole 8, and the effective area of the transparent electrode layer 5 is expanded. The output of the thin film solar cell 1 can be increased. And since the insulating tape 11 is arrange | positioned between the transparent electrode layer 5 and the 2nd back electrode layer 6 in the 2nd through-hole 8, the insulation in the 2nd through-hole 8 can also be ensured. .

  According to the method for manufacturing the thin-film solar cell 1 according to the first embodiment of the present invention, the step of forming the second through-hole 8 in the insulating substrate 2 and the back electrode layer on one surface 2a of the insulating substrate 2 3a, and forming the first back electrode layer 3b on the other surface 2b of the insulating substrate 2, and after forming the back electrode layer 3a and the first back electrode layer 3b, the insulating substrate 2 Forming a first through-hole 7 in the substrate, disposing an insulating tape 11 between the first back electrode layer and the second back electrode layer to close the second through-hole 8, and insulating properties Laminating the photoelectric conversion layer 4 and the transparent electrode layer 5 in this order from the one surface 2a side of the substrate 2 and laminating the second back electrode layer 6 from the other surface 2b side of the insulating substrate 2; The layers stacked on both surfaces 2a and 2b of the insulating substrate 2 are staggered. Forming the first and second patterning lines 9 and 10 and dividing the insulating substrate 2 into a plurality of unit cells, so that it is necessary to perform mask processing in the vicinity of the second through hole as in the prior art. The yield at the time of manufacturing the thin film solar cell 1 is improved.

In addition, since it is not necessary to perform mask processing in the vicinity of the second through-hole 8, the mask and the layer on the insulating substrate 2 do not come into contact with each other and the layer on the insulating substrate 2 is not damaged. Thereby, the leakage current does not increase in the thin film solar cell 1, and the defect rate when the thin film solar cell 1 is manufactured can be reduced.
[Second Embodiment]
Hereinafter, a thin film solar cell 1 according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a plan view of the thin-film solar cell according to the second embodiment. 5 is a cross-sectional view taken along line AA in FIG. 4, and (b) is an enlarged view of C in (a). 6 is a cross-sectional view taken along line BB in FIG. 4, and (b) is an enlarged view of D in (a). In addition, about the part similar to what was demonstrated by embodiment mentioned above, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

In the second embodiment, as shown in FIG. 4, a plurality of second through holes 8 are formed at intervals in the width direction of the insulating substrate 2.
8 to 10, since the transparent electrode layer 25 is partially formed, the second through holes 28 are provided only at both ends in the width direction of the insulating substrate 22. It was not possible to disperse and arrange in the width direction.

  According to the thin-film solar cell 1 of the second embodiment, the second through holes 8 can be distributed and arranged in the width direction of the insulating substrate 2, and the interval between the second through holes 8 can be reduced. Thereby, the Joule loss in the width direction of the substrate is reduced, and the output of the thin film solar cell 1 can be improved.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made based on the technical idea of the present invention.
In the above-described embodiment, when the second through hole 8 is provided, punching using a mold (perforation method) is used, but a step is provided in the second through hole 8 using a laser, The insulating resin 11 can be easily embedded in the second through hole 8.

  In the above-described embodiment, the step of applying the insulating tape 11 is performed immediately after the second through hole 8 is formed. However, after the second through hole 8 is formed, the transparent electrode layer 5 is formed. Any process can be applied as long as it is before. However, if it is performed in the order of the flowchart shown in FIG.

DESCRIPTION OF SYMBOLS 1 Thin film solar cell 2 Insulating substrate 3 Metal electrode layer 3a Back surface electrode layer 3b 1st back surface electrode layer 4 Photoelectric conversion layer 5 Transparent electrode layer 6 2nd back surface electrode layer 7 1st through-hole 8 2nd through-hole DESCRIPTION OF SYMBOLS 9 1st patterning line 10 2nd patterning line 11 Insulating tape 21 Substrate unwinding part 22 Substrate winding-up part 23 Insulating tape unwinding part 24 Insulating tape sticking part 25 Heat processing part 26 Conveyance roll

Claims (11)

  A back electrode layer, a photoelectric conversion layer, and a transparent electrode layer are laminated in this order on one surface of the insulating substrate, and a first back electrode layer and a second electrode layer are stacked on the other surface of the insulating substrate. Back electrode layers are stacked in this order, and the insulating substrate is divided into a plurality of unit cells by alternately forming pattern lines on the layers stacked on both sides of the insulating substrate, and the transparent electrode layer And the second back electrode layer are electrically connected through a first through-hole penetrating the insulating substrate, and the back electrode layer and the first back electrode layer are electrically insulating. In the thin film solar cell electrically connected through the second through hole penetrating the substrate and adjacent unit cells are connected in series, the insulating tape for closing the second through hole is a first tape. Pasted between the back electrode layer and the second back electrode layer Thin-film solar cells and the transparent electrode layer and the second back electrode layer is characterized in that it is electrically insulated by the insulating tape in the second through hole.   The thin film solar cell according to claim 1, wherein the insulating tape is a polyimide heat-resistant adhesive tape.   3. The thin film solar cell according to claim 1, wherein the insulating substrate is made of a film material.   The thin film solar cell according to claim 4, wherein the film material is a heat-resistant film of polyimide or polyimide amide.   5. The thin film solar according to claim 1, wherein the photoelectric conversion layer is one of an amorphous semiconductor, an amorphous compound semiconductor, a dye-sensitized solar cell, and an organic solar cell. battery.   Forming a second through hole in the insulating substrate; forming a back electrode layer on one surface of the insulating substrate; and forming a first back electrode layer on the other surface of the insulating substrate. A step of forming a first through hole in the insulating substrate after forming the back electrode layer and the first back electrode layer; and an insulating tape for closing the second through hole. The step of attaching between the first back electrode layer and the second back electrode layer, and laminating the photoelectric conversion layer and the transparent electrode layer in this order from one surface side of the insulating substrate, and the insulating property A step of laminating a second back electrode layer from the other surface side of the substrate, and patterning lines are alternately formed on the layers laminated on both surfaces of the insulating substrate, whereby the insulating substrate is formed into a plurality of unit cells. Dividing into Method of manufacturing a thin film solar cell according to symptoms.   After pasting an insulating tape for closing the second through hole on the first back electrode layer side, and before laminating the photoelectric conversion layer from one surface side of the insulating substrate, heating is performed. The method of manufacturing a thin-film solar cell according to claim 7, wherein the insulating tape is degassed by heating, and further, when the insulating tape is a thermosetting material, the insulating tape is heat-cured.   8. The method for manufacturing a thin-film solar cell according to claim 6, wherein the insulating tape is a heat-resistant adhesive tape of polyimide or polyimide amide.   7. The method for manufacturing a thin-film solar cell according to claim 6, wherein the insulating substrate is made of a film material.   10. The method for manufacturing a thin-film solar cell according to claim 9, wherein the film material is a heat-resistant film of polyimide or polyimide amide. The step of affixing an insulating tape for closing the second through-hole to the first back electrode layer side includes the second penetrating in a state in which the film material is partially wound around an unwinding roll or a transporting roll. An insulating tape for closing the hole is attached to the first back electrode layer side so as to cover the second through hole, and then the insulating tape is degassed by heating. Item 11. A method for producing a thin-film solar cell according to Item 9 or 10.