JP2003060219A - Thin film solar cell and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin film solar cell which is increased in effective power generating area by the use of a simple structure and a simple manufacturing method, and to provide a method of manufacturing the same. SOLUTION: A photoelectric conversion unit is composed of a first electrode layer 74, a photoelectric conversion layer 75, and a transparent electrode layer 76 which are successively laminated on the surface of a board 71, and a third electrode layer 73 and a fourth electrode layer 79 are formed on the back of the board 71 as connection electrode layers. The photoelectric conversion unit and the connection electrode layers are patterned on a unit part 5, while being shifted in relative position between them, and the unit cells patterned adjacent to each other on the surface are electrically connected in series via connection holes 78 and current-collecting holes 77 formed in a photoelectric conversion layer forming region, so as to form a thin film solar cell. The transparent electrode layer 76 is formed through the overall width of the unit part of the photoelectric conversion unit, and region isolating lines 41, which electrically isolate regions adjacent to the connection holes from the other regions containing the current collecting holes are provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thin film solar cell in which a plurality of unit cells are connected in series and a method for manufacturing the same.

[0002]

2. Description of the Related Art Currently, from the standpoint of environmental protection, research and development of clean energy is in progress. Above all, solar cells are attracting attention because of their unlimited resources (sunlight) and no pollution.

A typical example of a solar cell (photoelectric conversion device) in which a plurality of solar cell elements formed on the same substrate are connected in series is a thin film solar cell.

Thin-film solar cells are considered to be the mainstream of solar cells in the future because they are thin and lightweight, have low manufacturing costs, and can easily be made large in area. In addition to supplying electric power, roofs and windows of buildings are considered. Demand is also expanding for commercial and residential use, which are used by attaching to such things.

Conventional thin-film solar cells generally use a glass substrate. In recent years, research and development of a flexible solar cell using a plastic film has been promoted and put into practical use in terms of weight reduction, workability, and mass productivity. Further, a flexible metal material using an insulating film substrate has been developed. Taking advantage of this flexibility, mass production becomes possible by the roll-to-roll method and stepping roll method.

In the above thin film solar cell, a first electrode (hereinafter, also referred to as a lower electrode), a photoelectric conversion layer formed of a thin film semiconductor layer, and a second electrode (hereinafter, also referred to as a transparent electrode) are provided on an electrically insulating film substrate. A plurality of stacked photoelectric conversion elements (or cells) are formed. First of certain photoelectric conversion elements
By repeatedly electrically connecting the electrode and the second electrode of the adjacent photoelectric conversion element, a necessary voltage is output to the first electrode of the first photoelectric conversion element and the second electrode of the last photoelectric conversion element. be able to.

[0007] For example, in order to obtain AC of 100 V as a commercial power source by converting it into an alternating current by an inverter, it is desirable that the output voltage of the thin film solar cell is 100 V or more.
More than one element is connected in series. Recently, it has become easy to form 200V on a single substrate.

Such a photoelectric conversion element and its serial connection are formed by film formation of an electrode layer and a photoelectric conversion layer, patterning of each layer, and a combination procedure thereof. As an example of the configuration and manufacturing method of the above-mentioned solar cell, the applicant of the present invention has proposed a so-called SCAF (Series Connection throug).
h Apertures on Film) type thin film solar cells have been proposed. For example, JP-A-10-233517 and JP-A-2
No. 000-223727.

FIG. 5 shows an example of the thin-film solar cell described in Japanese Patent Laid-Open No. 10-233517, (a) is a plan view, (b) is a line ABCD and BQ in (a).
It is sectional drawing along C, (c) is E in (a).
The E sectional view is shown.

A first electrode layer, a photoelectric conversion layer, and a second electrode layer are sequentially laminated on a long film substrate made of an electrically insulating and flexible resin, and a first electrode layer, a photoelectric conversion layer, and a second electrode layer are laminated on the opposite side (back surface) of the film substrate. A back electrode is formed by stacking three electrode layers and a fourth electrode layer. The photoelectric conversion layer is, for example, a pin junction of amorphous silicon. As the material for the film substrate, a polyimide film, for example, a film having a thickness of 50 μm is used.

Other materials for the film include polyethylene naphthalate (PEN) and polyether sulfone (PEN).
ES), polyethylene terephthalate (PET), or aramid-based film can be used.

Next, an outline of the manufacturing process will be described below.

First, a connection hole h1 is opened in a film substrate by using a punch, and silver is sputtered as a first electrode layer on one side (front side) of the substrate to a thickness of, for example, 100 nm. On the side opposite (to the back side),
Similarly, a silver electrode is formed as an electrode layer. The first electrode layer and the third electrode layer overlap with each other on the inner wall of the connection hole h1 and are electrically connected.

As the electrode layer, in addition to silver (Ag), Al, C
A metal such as u or Ti may be formed by sputtering or electron beam evaporation, or a metal oxide film and a metal multilayer film may be used as an electrode layer. After the film formation, on the front side, the first electrode layer is laser processed into a predetermined shape to pattern the lower electrodes 11 to 16. Adjacent parts of the lower electrodes l1 to l6 are separated by a single separation line g2.
In order to separate the two rows of photoelectric conversion elements connected in series and the peripheral conductive portion f from each other, two separation lines g2 are formed, and the lower electrodes 11 to 16 are surrounded by the separation lines. After punching the current collecting hole h2 again using the punch, an a-Si layer is formed as a photoelectric conversion layer p on the front side by plasma CVD. A film having a width W2 is formed using a mask, and the same separation line as the first electrode layer is formed only between the two-row elements by laser processing. The width W2 may extend over the connection hole h1.

Further, a transparent electrode layer (ITO layer) is formed on the front side as a second electrode layer. However, a mask is placed between the two element rows and on both side portions of the substrate parallel to the element rows to connect holes h1.
Do not form a film on the substrate, but only on the element portion. As the transparent electrode layer, in addition to ITO (indium sulphite), Sn
An oxide conductive layer such as O ₂ or ZnO can be used.

Next, a layer made of a low resistance conductive film such as a metal film is formed as a fourth electrode layer on the entire back surface. Due to the film formation of the fourth electrode, the second electrode and the fourth electrode are overlapped with each other on the inner wall of the current collecting hole h2 and are electrically connected. On the front side, a separation line having the same pattern as that of the lower electrode is formed by laser processing, and individual second electrodes u1
To u6 are formed, the third electrode and the fourth electrode are laser-processed simultaneously on the back side, the connection electrodes e12 to e56 and the power extraction electrodes o1 and o2 are individualized, and the front side separation line g3 is formed on the peripheral portion of the substrate. Form the separation line g2 so as to overlap,
One separation line is formed between adjacent electrodes.

There is a separation line g3 (inside the peripheral conductive portion f) at the peripheral edge that collectively encloses all the thin film solar cell elements and at the adjacent boundary between the two rows of series-connected solar cell elements. There are no layers in the separation line g3. On the back side, there is a separation line g2 (inside the peripheral conductive portion f) at the peripheral edge that collectively surrounds all the electrodes and at the adjacent boundary between the two rows of series-connected electrodes. There are no layers in the separation line g2.

Thus, the power take-out electrode o1-the current collecting hole h2-the upper electrode u1, the photoelectric conversion layer, the lower electrode l1-the connecting hole h
1-connection electrode e12-upper electrode u2, photoelectric conversion layer, lower electrode l2-connection electrode e23 -...- upper electrode u6, photoelectric conversion layer, lower electrode l6-connection hole h1-power extraction electrode o2 in this order The series connection of conversion elements is completed.

Since the third electrode layer and the fourth electrode layer are electrically at the same potential, they may be collectively treated as one connection electrode layer in the following description for convenience of description.

FIG. 6 is a perspective view showing a simplified structure of the thin-film solar cell in order to facilitate understanding of the structure. In FIG. 6, the unit photoelectric conversion element 62 formed on the front surface of the substrate 61 and the connection electrode layer 63 formed on the back surface of the substrate 61 are each completely separated into a plurality of unit units, and are formed by shifting their respective separation positions. ing. Therefore, the current generated in the photoelectric conversion layer 65, which is the amorphous semiconductor portion of the element 62, is first collected in the transparent electrode layer 66, and then the current collecting hole 67 formed in the transparent electrode layer region.
(H2) to the connection electrode layer 63 on the back surface, and further through the connection hole 68 (h1) for series connection formed outside the transparent electrode layer region of the device in the connection electrode layer region to the above device. The lower electrode layer 64 extending to the outside of the transparent electrode layer region of the adjacent element is reached, and both elements are connected in series.

A simplified manufacturing process of the thin film solar cell is shown in FIGS. 7 (a) to 7 (g). Plastic film 71
As a substrate (step (a)), a connection hole 78 is formed therein (step (b)), and the first electrode layer (lower electrode) is formed on both surfaces of the substrate.
After forming 74 and the third electrode layer (a part of the connection electrode) 73 (step (c)), a current collecting hole 77 is formed at a position separated from the connection hole 78 by a predetermined distance (step (d)). Process (c)
Between step (d) and step (d), there is a step of patterning the lower electrode by laser processing the first electrode layer (lower electrode) 74 into a predetermined shape, but the illustration of this step is omitted here. .

Next, a semiconductor layer 75 to be a photoelectric conversion layer and a transparent electrode layer 76 to be a second electrode layer are sequentially formed on the first electrode layer 74 (steps (e) and (f)). A fourth electrode layer (connection electrode layer) 79 is formed on the third electrode layer 73 (step (g)). After that, the thin films on both sides of the substrate 71 are separated and processed using a laser beam to form a series connection structure as shown in FIG.

In FIG. 7, the connection between the transparent electrode layer 76 and the fourth electrode layer 79 in the current collecting hole h2 is shown as two layers by stacking the respective layers, but in FIG. , Electrically treated as one layer, and shown as one layer.

For convenience of explanation of the present invention, FIG. 4 is a schematic view in which the structure of the conventional thin film solar cell having the SCAF structure is further simplified, and in particular, attention is paid to an end portion of the thin film solar cell including the connection hole. . FIG. 4A is a plan view, FIG.
(C) shows a side sectional view, respectively. In FIG. 4, members having the same functions as those shown in FIG. 7 (or FIGS. 5 and 6) are designated by the same reference numerals and the description thereof will be omitted.

The structural points related to the explanation of the present invention of the thin film solar cell shown in FIG. 4 are as follows. That is, when the transparent electrode layer 76 is formed, a metal mask is used to form the non-power generation region SA where the transparent electrode layer 76 is not attached in the vicinity of the connection holes 78 (h1, 68). In the illustrated example, the photoelectric conversion unit includes a large number of current collecting holes 77 (h2, 67).
Of the connecting electrode layers (73 and 7).
9) is divided into a plurality of unit parts by a laser beam or the like.

With the above structure, as described above, the first electrode layer 7 is formed in the connection holes 78 (h1, 68) at the time of forming each electrode.
4 and the connection electrode layer, the current collecting holes 77 (h2, 67)
In the inside, the transparent electrode layer 76 and the connection electrode layer are electrically connected to each other, and in the end, the transparent electrode layer 76 is electrically connected to the first electrode layer 74 of the adjacent unit cell via the connection electrode layer and is connected in series. A connection structure is formed.

[0027]

By the way, the above SCA
The F structure thin film solar cell and its manufacturing method have the following problems.

As described above, the reason why the non-power generation area SA where the transparent electrode layer 76 does not adhere is provided in the vicinity of the connection holes 78 (H1, 68) by using the metal mask is that the connection holes 78 (H1, 68).
This is to prevent the transparent electrode layer 76 and the first electrode layer 74 from coming into contact with each other in 68). This is because if the transparent electrode layer 76 and the first electrode layer 74 contact each other in the same unit cell, the solar cell will be in a short-circuit state and no power will be generated.

However, when the area SA is formed by using the metal mask as described above, the area of the area SA occupies a non-negligible ratio with respect to the unit cell area. The amorphous semiconductor (photoelectric conversion layer) and the transparent electrode layer 76 and the first
The region sandwiched by the electrode layer 74 is a power generation region, and the region SA where the transparent electrode layer 76 is not deposited is a region that does not generate power, that is, a non-power generation region, so that the effective power generation area is reduced.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a thin film solar cell having an effective power generation area increased by a simple structure and a manufacturing method, and the same. It is to provide a manufacturing method.

[0031]

In order to solve the above-mentioned problems, according to the invention of claim 1, a first electrode layer as a lower electrode layer, a photoelectric conversion layer, and a transparent layer are formed on the surface of a substrate having electrical insulation properties. A photoelectric conversion part formed by sequentially laminating electrode layers (second electrode layers), and a third electrode as a connection electrode layer formed on the back surface of the substrate.
An electrode layer and a fourth electrode layer, wherein the photoelectric conversion section and the connection electrode layer are patterned in unit portions with their positions displaced from each other, and the connection hole and the current collection hole formed in the photoelectric conversion layer formation region are formed. In the thin-film solar cell, in which unit photoelectric conversion portions (unit cells) that are patterned and adjacent to each other on the surface are electrically connected in series, the transparent electrode layer is a unit portion full width of the photoelectric conversion portion. A region separation line that is formed over the entire area and electrically separates the region near the connection hole from the other region including the current collecting hole is provided.

Further, in the thin-film solar cell according to claim 1, the region separation line of the transparent electrode layer is approximately 4 times a unit cell separation line for patterning the unit portion.
It has an inclination angle of 5 degrees (the invention of claim 2).

According to the first or second aspect of the present invention, the effective power generation area increases as the formation area of the transparent electrode layer increases. In particular, according to the invention of claim 2, in the case of a normal solar cell pattern in which the unit cell has a rectangular shape, a rectangular shape having the same side length is formed by forming a triangular non-power generation region at an angle of about 45 degrees. The area of the non-power generation region is further reduced as compared with the case of forming the non-power generation region.

Further, as a method of manufacturing the thin film solar cell, the invention of claim 3 is suitable. That is, the method for manufacturing a thin film solar cell according to claim 1 or 2 includes the following steps 1) to 6). 1) A step of forming a connection hole in a substrate, forming a first electrode layer on the front surface of the substrate, and forming a third electrode layer on the back surface. 2) A step of forming a current collecting hole in the substrate. 3) On the inner surface of the first electrode layer and the connection hole and the current collecting hole,
A step of forming a photoelectric conversion layer. 4) After forming a linear mask having a predetermined width at a predetermined position where the region separation line is to be formed, a transparent electrode layer is formed on the photoelectric conversion layer and on the photoelectric conversion layer on the inner surface of the connection hole and the current collecting hole. Forming step. 5) A step of forming a fourth electrode layer on the third electrode layer, on the photoelectric conversion layer on the inner surface of the connection hole and on the transparent electrode layer on the inner surface of the current collecting hole. 6) A step of collectively patterning the photoelectric conversion part on the front surface of the substrate and the connection electrode layer on the back surface of the substrate into unit parts.

Further, in the method of manufacturing a thin film solar cell according to claim 3, the linear mask has an inclination angle of about 45 degrees with a unit cell separation line for patterning the unit portion, and the mask. Is extended to adjacent unit portions and provided over a plurality of unit portions (the invention of claim 4). Thereby, as shown in FIG. 6, when the connection hole is provided facing the end of the solar cell,
The separation lines at the upper and lower ends can be collectively formed, which facilitates manufacturing.

Further, from the viewpoint of facilitating manufacturing, a manufacturing method as claimed in claim 5 can be adopted.
That is, in the method of manufacturing a thin-film solar cell according to claim 3, instead of forming the area separation line by forming a linear mask having a predetermined width at a predetermined position where the area separation line is to be formed. Then, after forming the transparent electrode layer, the region separation line is formed by patterning.

In this case, it is necessary to pattern the transparent electrode layer so as not to damage the photoelectric conversion layer. For that purpose, for example, a method of patterning by etching is preferable.

Further, as the thin film solar cell for reducing the area of the non-power generation region near the connection hole and increasing the effective power generation region and the manufacturing method thereof, the inventions of the following claims 6 and 7 are also preferable.

That is, in the thin film solar cell according to claim 1, in place of the transparent electrode layer provided with the region separation line, an island-shaped region near the connection hole is masked, and the masked island-shaped region is formed. Except for this, a transparent electrode layer is formed over the entire width of the unit portion of the photoelectric conversion section (the invention of claim 6). 7. The method of manufacturing a thin-film solar cell according to claim 6, wherein the island-shaped region is a mask unit of a thin-film forming mask in which a plurality of mask units corresponding to the island-shaped regions are provided on a support. It is formed in contact with the surface (the invention of claim 7).

A thin film forming mask provided with the mask unit and a method of manufacturing a thin film solar cell using the same have been filed by the same applicant in Japanese Patent Application No. 2001-305123. Details of the manufacturing method using the island-shaped region and the mask unit in the invention will be described later.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a thin-film solar cell according to the present invention and an embodiment relating to a method for manufacturing the same, and is a diagram corresponding to FIG. In FIG. 1, the same functional members as those of the thin film solar cell shown in FIG.

In the thin film solar cell shown in FIG. 1, the steps up to the formation of the photoelectric conversion layer 75 and the steps after the formation of the fourth electrode layer 79 are basically the same as the steps shown in FIG. In the following examples, the outline of all steps including the materials used will be described below. That is, first, a polyimide film having a film thickness of 50 μm is formed on the substrate 71.
Prepared as 2mm diameter by punching device on film substrate
The connection holes 78 (h1, 68) of No. 1 were formed. An Ag film as the first electrode layer 74 and the third electrode layer 73 was sequentially formed on the both surfaces of the film substrate to have a thickness of 300 nm by the sputtering method. As a result, the first electrode layer 74 and the third electrode layer 73 are connected to the connection hole 78 (H1, 68).
Contacted inside and electrically connected. With a punching device, a current collecting hole 77 (h with a diameter of 1 mm
2, 67) were formed in plural. An amorphous semiconductor layer 75 to be a photoelectric conversion layer was formed with a thickness of about 1 μm by a plasma CVD apparatus. Next, a thin linear mask is placed at the position of the area separation line 41 in FIG. 1 so that the connection holes 78 (h1, 68) and the current collection holes 77 (h2, 67) in the same unit cell are separated. The transparent electrode layer 76 was formed in the state of being in close contact. The material of the transparent electrode layer 76 is ITO (indium tin oxide)
And formed by the sputtering method. The linear mask prevents the transparent electrode layer 76 from being formed under the mask,
The transparent electrode layer 76 in the unit cell is connected to the connection hole 78 (h
1, 68) and a connection electrode area (TA) and a current collecting hole 77
A region (TB) including (h2,67) is separated.

The connection electrode area TA is an area for connecting in series and does not contribute to power generation (transparent electrode layer 7).
6, because the first electrode layer 74 and the connection electrode layer are all electrically short-circuited). Therefore, the connection electrode area TA
As the area ratio of the unit cells is reduced, the effective power generation area is increased and the solar cell output is increased. Therefore, in the case of the normal pattern in which the unit cells are rectangular, the unit cell separation line 31 is formed as shown in FIG. The regions TA and TB are separated by making an angle of about 45 degrees.

After forming the transparent electrode layer 76, a series-connected solar cell was manufactured again by the following process as in the conventional example. A Ni film was formed as the fourth electrode layer 79 by a sputtering method. The front side (photoelectric conversion layer side) of the film substrate was scribed with a laser beam to form the unit cell separation line 31, and the unit cell was patterned. The connection electrode layer (the third electrode layer 73) on the back surface side of the film substrate.
And dividing the fourth electrode layer 79) with a laser beam,
The separation line 32 was formed and patterned. The separation line 32 of the connection electrode layer was formed at a position offset from the separation line 31 of the unit cell.

In the present embodiment, the area separation line 41 for separating the areas TA and TB in one unit cell extends into the area TB of the adjacent unit cell to form the transparent electrode layer in TB. I showed an example of separating 76,
In each of the separated regions, the transparent electrode layer 76 is electrically connected to the connection electrode layer through the current collecting holes 77 (H2, 67), so that there is no problem in forming a serial connection structure. Absent.

The region separating line 41 can be formed so as to be retained in each unit cell without extending to the adjacent unit cell. However, when the connection hole is provided facing the end of the solar cell. 1 has an advantage of simplifying manufacturing if it is formed by extension as shown in FIG. 1 and the separation lines near the connection holes at the upper and lower ends are collectively formed.

Next, the embodiments relating to the inventions of claims 6 and 7 will be described below with reference to FIGS. 2 and 3. FIG. 2 shows a plan view of a thin-film solar cell corresponding to FIG. 1A and different from FIG. 1, and shows an example in which there are a total of nine unit photoelectric conversion portions (unit cells) in a matrix. Figure 2
In FIG. 1, the hatched plane portion 76 indicates the transparent electrode layer, and the rectangular island-shaped region close to the square indicated by SA indicates the connection electrode region (non-power generation region) indicated by TA in FIG. In FIG. 2, reference numeral 31 indicates a unit cell separation line, and reference numerals 77 and 78 indicate connection holes and current collecting holes, respectively.

Next, a method of manufacturing the thin-film solar cell shown in FIG. 2 will be described, except that the thin film of the transparent electrode layer having the island-shaped region SA in FIG. 2 is formed by using a mask described later. Since it is the same as the manufacturing process of the thin-film solar cell described in (1), only the method of forming a thin film having island regions will be described below.

As described above, regarding the thin film forming mask having the mask unit and the method of manufacturing a thin film solar cell using the same, the same applicant filed Japanese Patent Application No. 2001-30.
No. 5123 has been filed. 3A and 3B are schematic views showing a mask for forming a thin film described in the same item, FIG. 3A is a plan view, and FIG. 3B is a side sectional view.

The thin film forming mask shown in FIG. 3 is composed of a mask unit 1 and a support 2 for supporting it.
The mask unit 1 having a circular cross section in FIG.
It is possible to simplify the manufacturing process by forming a thin film having an island-shaped area SA in accordance with the arrangement of the island-shaped areas and having a rectangular cross-section in accordance with the rectangular island-shaped areas. At the same time, the occurrence of defects such as pinholes is suppressed and the yield is also improved (for details of the thin film forming mask including the mask unit, see Japanese Patent Application No. 2001-305123).

As described above, in the embodiment shown in FIG. 2, the substantially square unit cells are connected in series and the connection hole 78 is formed.
The transparent electrode layer is formed by masking only the island-shaped area SA around the area. As an example, 128 series (8 columns x 16 rows) with a square unit cell of 5 cm x 5 cm.
When the thin film solar cell of No. 1 is manufactured, the size of each mask unit is sufficient to be 0.6 cm × 0.6 cm, and the area of the non-power generation region by 128 mask units is 46.1 cm.
It becomes ² . A trial calculation of the area loss of the effective area of the power generation region in this case is 1.4%. In the case of the conventional configuration of FIG. 4, the area loss is about 6%, and according to the embodiment of FIG. 2, the area of the non-power generation region can be significantly reduced.

[0053]

According to the present invention, the first electrode layer as the lower electrode layer, the photoelectric conversion layer, the transparent electrode layer (the second electrode layer) are formed on the surface of the electrically insulating substrate by the above manufacturing method. ) Are sequentially laminated, and a third electrode layer and a fourth electrode layer as connection electrode layers formed on the back surface of the substrate.
An electrode layer, wherein the photoelectric conversion portion and the connection electrode layer are displaced from each other and patterned into unit parts,
A thin-film solar cell in which unit photoelectric conversion portions (unit cells) that are patterned and adjacent to each other on the surface are electrically connected in series through a connection hole and a current collection hole formed in the photoelectric conversion layer formation region. In the battery, the transparent electrode layer is formed over the entire width of a unit portion of the photoelectric conversion unit, and provided with a region separation line that electrically separates a region near the connection hole from another region including the current collecting hole. Or instead of the transparent electrode layer provided with the region separation line, an island-shaped region near the connection hole is masked, and the unit of the photoelectric conversion unit is removed except for the masked island-shaped region. Since the transparent electrode layer is formed over the entire width of the part, with the expansion of the transparent electrode layer forming area,
The effect of increasing the effective power generation area can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a thin film solar cell according to an embodiment of the present invention.

FIG. 2 is a plan view of a thin film solar cell according to another embodiment of the present invention.

FIG. 3 is a schematic diagram showing a mask for forming a thin film used for manufacturing the embodiment of FIG.

FIG. 4 is a schematic diagram of a conventional thin film solar cell.

FIG. 5 is a diagram showing an example of a configuration of a SCAF type thin film solar cell.

FIG. 6 is a perspective view showing a schematic configuration of a SCAF type thin film solar cell.

FIG. 7 is a diagram showing an outline of a manufacturing process of a SCAF type thin film solar cell.

[Explanation of symbols]

5: unit part, 31: unit cell separation line, 32:
Connection electrode layer separation line, 41: area separation line, 7
1: substrate, 73: third electrode layer, 74: first electrode layer, 7
5: Photoelectric conversion layer, 76: Transparent electrode layer, 77: Current collecting hole, 7
8: Connection hole, 79: Fourth electrode layer, SA: Island region, T
A: connection electrode area, TB: area including current collecting holes.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5F051 AA05 BA12 CA15 CB15 CB27                       EA02 EA09 EA10 EA11 EA20                       FA04 FA06 GA05

Claims (7)

[Claims] 1. A first electrode layer as a lower electrode layer, a photoelectric conversion layer, and a transparent electrode layer (second electrode layer) on the surface of a substrate having electrical insulation properties.
An electrode layer) and a third electrode layer and a fourth electrode layer as a connection electrode layer formed on the back surface of the substrate, and the photoelectric conversion unit and the connection electrode layer are positioned relative to each other. Are patterned to form a unit portion, and the adjacent unit photoelectric conversion portions (unit cells) that are patterned on the surface and are adjacent to each other are formed through the connection hole and the current collecting hole formed in the photoelectric conversion layer forming region. In a thin film solar cell electrically connected in series, the transparent electrode layer is formed over the entire unit portion width of the photoelectric conversion portion, and a region near the connection hole and another region including the current collecting hole. A thin film solar cell, characterized in that it is provided with a region separation line that electrically separates. 2. The thin film solar cell according to claim 1, wherein
The thin film solar cell, wherein the region separation line of the transparent electrode layer has an inclination angle of about 45 degrees with the unit cell separation line for patterning the unit portion. 3. A method of manufacturing a thin film solar cell according to claim 1, comprising the following steps 1) to 6). 1) A step of forming a connection hole in a substrate, forming a first electrode layer on the front surface of the substrate, and forming a third electrode layer on the back surface. 2) A step of forming a current collecting hole in the substrate. 3) On the inner surface of the first electrode layer and the connection hole and the current collecting hole,
A step of forming a photoelectric conversion layer. 4) After forming a linear mask having a predetermined width at a predetermined position where the area separation line is to be formed, a transparent electrode layer is formed on the photoelectric conversion layer and on the photoelectric conversion layer on the inner surface of the connection hole and the current collecting hole. Forming step. 5) A step of forming a fourth electrode layer on the third electrode layer, on the photoelectric conversion layer on the inner surface of the connection hole and on the transparent electrode layer on the inner surface of the current collecting hole. 6) A step of collectively patterning the photoelectric conversion part on the front surface of the substrate and the connection electrode layer on the back surface of the substrate into unit parts. 4. The method of manufacturing a thin film solar cell according to claim 3, wherein the linear mask has an inclination angle of about 45 degrees with a unit cell separation line for patterning the unit portion, and the mask is A method for manufacturing a thin-film solar cell, characterized in that the thin film solar cell is provided so as to extend to adjacent unit portions and to extend over a plurality of unit portions. 5. The method for manufacturing a thin-film solar cell according to claim 3, wherein the area separation line is formed by forming a linear mask having a predetermined width at a predetermined position where the area separation line is to be formed. Instead, after forming the transparent electrode layer, a region separation line is formed by patterning, a method for manufacturing a thin film solar cell. 6. The thin film solar cell according to claim 1,
Instead of the transparent electrode layer provided with the region separation line,
A thin-film solar cell, wherein an island-shaped region near the connection hole is masked, and a transparent electrode layer is formed over the entire unit portion width of the photoelectric conversion unit except for the masked island-shaped region. 7. The method of manufacturing a thin-film solar cell according to claim 6, wherein the island-shaped region has a mask unit corresponding to a plurality of the island-shaped regions on a support body. A method for manufacturing a thin-film solar cell, comprising: forming a thin film solar cell in contact with a substrate surface.