JP4568531B2 - Integrated solar cell and method of manufacturing integrated solar cell - Google Patents

Description

  The present invention relates to an integrated solar cell having an intermediate layer.

A solar cell (single cell) including a power generation unit in which a lower electrode, a single-layer photoelectric conversion cell made of a semiconductor, and an upper electrode are sequentially formed on an insulating substrate is known. This solar cell formed as a single cell has a drawback that long wavelength light having energy lower than the band gap of the semiconductor is transmitted or reflected without being absorbed by the semiconductor. In addition, short-wavelength light having energy larger than the band gap is absorbed and contributes to power generation, but excess energy beyond the band gap becomes heat and is not used. Therefore, there is a method of using a plurality of semiconductors having different band gaps in order to increase the efficiency of the solar cell. As described above, solar cells using a plurality of stacked semiconductors include tandem solar cells in which cells having different absorption wavelength bands are stacked in two stages, and triple solar cells in which three stages are stacked. As the tandem solar cell, a thin-film silicon tandem solar cell using a-Si (amorphous silicon) for the top cell on the sunlight incident side, crystalline Si or a-SiGe for the bottom cell on the back side, and CuGaSe for the top cell. _2. A thin film compound tandem solar cell using CuIn _x Ga _1-x Se ₂ for the bottom cell is known. As a triple solar cell, a thin-film silicon triple solar cell using a-SiC for the top cell, a-Si for the middle cell provided between the top cell and the bottom cell, and a-SiGe for the bottom cell is known. Taking a tandem solar cell using a-Si as a top cell and crystalline Si (for example, microcrystalline silicon in which an amorphous phase is mixed) as a bottom cell as an example, a-Si on the sunlight incident side is short. Crystalline Si absorbs light of a wavelength and absorbs light of a long wavelength that is not absorbed. Since the top cell and the bottom cell are electrically in series, the same amount of current flows through both cells, but the current of the tandem solar cell is determined by a-Si, which has a small generated current. Although the current can be increased by increasing the film thickness of a-Si and increasing the amount of light absorption, there is a problem that the light deterioration increases. Therefore, the light having a short wavelength that cannot be absorbed by a-Si is transmitted to the a-Si film side by the transparent intermediate layer, and the optical path is lengthened and absorbed, thereby increasing the film thickness of a-Si. The generated current can be increased.

This transparent intermediate layer is the same as the transparent electrode used for the lower electrode or the upper electrode on the light incident side of the solar cell, such as zinc oxide (ZnO), tin oxide (SnO ₂ ), and indium tin oxide (ITO). An object is a main component and is generally a low resistance film. The conductivity of the transparent metal oxide has the property of changing depending on the oxygen deficiency and doping element content.

The specific resistance of the transparent electrode is low, about 5 × 10 ⁻⁴ Ω · cm, but about two orders of magnitude higher than the specific resistance of the metal film used for the back electrode. Therefore, power loss occurs while the current generated in the cell flows through the transparent electrode. This is more noticeable as the substrate area becomes larger, and an integrated structure is known that reduces the loss in order to reduce the power that can be extracted to the outside. FIG. 1 shows a sectional view of an integrated solar cell having such an integrated structure. In this integrated solar cell, a plurality of solar cells (power generation units) are formed on one substrate and connected in series.

  A lower electrode 2, a lower photoelectric conversion cell 3, a transparent intermediate layer 4, an upper photoelectric conversion cell 5, and an upper electrode 6 are formed as a laminated film on the insulating substrate 1, and these laminated films constitute a power generation film. A transparent electrode is used for the lower electrode 2 or the upper electrode 6 on the light incident side. The power generation film is divided into a plurality of power generation units by the lower electrode separation groove 7 and the upper electrode separation groove 9. Further, between the adjacent power generation units, the lower electrode 2 of one power generation unit and the upper electrode 6 of the other power generation unit are extended, and are electrically connected at the connection groove 8 so that the respective power generation units are connected in series. It is connected. This is to reduce the amount of current flowing through the transparent electrode by dividing the power generation film and reducing the area of one power generation unit, and by increasing the voltage by serialization, the loss is suppressed. The separation grooves and connection grooves are formed by laser scribing so as to extend in a direction perpendicular to the series connection direction (a direction perpendicular to the paper surface).

  Solar cells include a super straight type in which sunlight enters from the lower side of FIG. 1 and a substrate type in which sunlight enters from the upper side of the figure. The super straight type solar cell includes a transparent substrate 1 such as glass, a transparent electrode used as the lower electrode 2, a top cell that absorbs a short wavelength region used as the lower photoelectric conversion cell 3, and an upper photoelectric conversion cell 5. It comprises a bottom cell that absorbs the long wavelength region used and a back electrode made of a metal film used as the upper electrode 6. In the substrate type solar cell, since the substrate 1 does not need to be transparent, a metal or a polymer film is also used in addition to glass. The substrate type solar cell is used as a substrate 1, a back electrode made of a metal film used as the lower electrode 2, a bottom cell that absorbs a long wavelength region used as the lower photoelectric conversion cell 3, and an upper photoelectric conversion cell 5. A top cell that absorbs a short wavelength region and a transparent electrode used as the upper electrode 6 are configured.

An integrated thin-film silicon tandem solar cell in which a transparent intermediate layer is inserted is disclosed in Patent Document 1, Patent Document 2, and the like. In these, the specific resistance value of the intermediate layer is defined, and 1 × 10 ⁻¹ Ω · cm or less is considered good. When the specific resistance of the intermediate layer is low, as indicated by an arrow 10 in FIG. 1, a part of the current that should flow from the upper photoelectric conversion cell to the lower photoelectric conversion cell passes through the intermediate layer and covers the connection groove 8. There is a problem that leaks. This current leakage is called side leakage because it flows laterally along the film.

  An example of an integrated structure for preventing side leakage is disclosed in Patent Document 3. In this integrated structure, a separation groove for removing the lower photoelectric conversion cell and the transparent intermediate layer is provided between the lower electrode separation groove 7 and the connection groove 8 in FIG. 1 so that the intermediate layer passes from the power generation unit to the connection groove 8. Current path is interrupted. However, in this integrated structure, there are problems that the number of separation grooves increases, the area of the connection portion that does not contribute to power generation increases, and an additional laser processing apparatus is required.

JP 2001-274430 A

JP 2002-118273 A

JP 2002-261308 A

  The present invention has been made in view of such circumstances, and provides an integrated solar cell that prevents side leakage without increasing the number of separation grooves that increase the ineffective area due to the connecting portion and increase the laser processing step. The purpose is to do.

In order to solve the above problems, an integrated solar cell of the present invention has an insulating substrate and a plurality of power generation units, and at least one power generation unit is provided on the insulating substrate, Provided on a plurality of photoelectric conversion cells stacked on the lower electrode, a transparent intermediate layer provided between two of the plurality of photoelectric conversion cells, and the plurality of photoelectric conversion cells. And the upper electrode is in electrical contact with the lower electrode of another adjacent power generation unit, the transparent intermediate layer is an oxide, and the specific resistance of the transparent intermediate layer is 20 Ω · cm. Ri der inclusive 100 [Omega · cm, the transparent intermediate layer you contact with the upper electrode without being divided.

  The lower electrode has a transparent oxide film, the upper electrode has a metal film, and the plurality of photoelectric conversion cells have an amorphous silicon film having a PIN junction, and the amorphous It is preferable to include a photoelectric conversion cell including a crystalline silicon film having a PIN junction located above a photoelectric conversion cell having a crystalline silicon film.

  The at least one power generation unit electrically connects a lower electrode separation unit that separates the lower electrode from a lower electrode of another power generation unit adjacent to the lower electrode, and a lower electrode of another power generation unit adjacent to the upper electrode. And at least one power generation unit and the adjacent other power generation unit are connected in series with each other and an upper electrode separation portion that separates an upper electrode of the other power generation unit adjacent to the upper electrode. The

The lower electrode separation part may be a lower electrode separation groove formed by removing a part of a lower electrode layer formed in common to the plurality of power generation units.
The connecting portion is configured to separate the plurality of photoelectric conversion cells and transparent intermediate layers of the at least one power generation unit from the plurality of photoelectric conversion cells and transparent intermediate layers of the other adjacent power generation units. A connection groove formed by removing a part of a laminated film having a plurality of layers for photoelectric conversion cells and a layer for a transparent intermediate layer formed in common in the unit, and extending to the connection groove And a part of the lower electrode of the other adjacent power generation unit that extends in the connection groove and is electrically connected to the part of the upper electrode.
The upper electrode separation part may be an upper electrode separation groove formed by removing a part of the upper electrode layer formed in common to the plurality of power generation units.

The transparent intermediate layer includes zinc oxide (ZnO), tin oxide (SnO ₂ ), indium tin oxide (ITO), copper aluminum oxide (CuAlO ₂ ), titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), oxide It can be formed of a material containing at least one selected from the group consisting of zirconium (ZrO ₂ ), aluminum oxide (Al ₂ O ₃ ), and gallium oxide (Ga ₂ O ₃ ).

  The integrated solar cell of the present invention may be an integrated tandem solar cell in which the plurality of photoelectric conversion cells are two photoelectric conversion cells, or an integration in which the plurality of photoelectric conversion cells are three photoelectric conversion cells. A type triple solar cell may be used.

The integrated solar cell of the present invention includes a step of forming a lower electrode layer on an insulating substrate, a part of the lower electrode layer is removed to form a lower electrode separation groove, and the lower electrode separation groove Forming a plurality of lower electrodes separated by a plurality of layers, and a plurality of layers for photoelectric conversion cells and two of the plurality of layers on the plurality of lower electrodes and the lower electrode separation grooves A step of forming a laminated body including a layer for an intermediate transparent intermediate layer, and removing a part of the laminated body in the vicinity of the lower electrode separation groove to form a connection groove, separated by the connection groove, Forming a plurality of laminated films each having a plurality of photoelectric conversion cells and a transparent intermediate layer provided between two of the plurality of photoelectric conversion cells on the plurality of lower electrodes Adjacent to the bottom of the connection groove A step of exposing a part of the partial electrode, a step of forming a layer for the upper electrode on the plurality of laminated films, the connection groove, and the exposed lower electrode, and the connection in the vicinity of the connection groove Above the lower electrode partially exposed in the groove, a part of the upper electrode layer is removed to form an upper electrode separation groove, and a plurality of upper electrodes separated by the upper electrode separation groove are formed. wherein the plurality of produced by the process comprising the steps of forming on each of the laminated films, a layer for the transparent intermediate layer has a specific resistance is formed below the transparent oxide material 20 [Omega · cm or more 100 [Omega · cm, the laminate The step of forming a body does not include a process of dividing the layer for the transparent intermediate layer.

The lower electrode layer may be formed using a transparent oxide.
The upper electrode layer can be formed using a metal material.
The plurality of layers for the photoelectric conversion cell may include an amorphous silicon layer having a PIN junction and a crystalline silicon layer positioned above the amorphous silicon layer and having a PIN junction.

The transparent material forming the layer for the intermediate layer includes zinc oxide (ZnO), tin oxide (SnO ₂ ), indium tin oxide (ITO), copper aluminum oxide (CuAlO ₂ ), titanium oxide (TiO ₂ ), A material containing at least one selected from the group consisting of silicon oxide (SiO ₂ ), zirconium oxide (ZrO ₂ ), aluminum oxide (Al ₂ O ₃ ), and gallium oxide (Ga ₂ O ₃ ) is preferable.

  When an integrated tandem solar cell is manufactured, two layers for the photoelectric conversion cell may be formed.

  When an integrated triple solar cell is manufactured, three layers for the photoelectric conversion cell may be formed.

  In the integrated solar cell of the present invention, the single film specific resistance of the transparent intermediate layer is 20 Ω · cm or more and 100 Ω · cm or less, so that the influence of side leakage in the integrated structure is reduced, and the efficiency, FF, and open circuit voltage are good. Become.

  By using a high-resistance transparent intermediate layer, the influence of side leakage is negligibly small, so power generation is achieved with the lower electrode separation groove, connection groove, and upper electrode separation groove without dividing the transparent intermediate layer. A conventional module structure in which the units are connected in series can be used. Therefore, the integrated solar cell of the present invention can be manufactured at a low cost because there is no increase in the invalid area of the connection portion due to the increase in the number of separation grooves, and there is no increase in the laser processing step.

  Embodiments of the integrated solar cell of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing an example of an integrated tandem solar cell. This integrated tandem solar cell shows the structure of a conventional integrated tandem solar cell, and also shows the structure of an embodiment of the integrated solar cell of the present invention. This integrated tandem solar cell has a super straight type structure, and is made of an insulating substrate 1 made of glass, a lower electrode 2 made of a transparent electrode such as SnO _2, and a-Si (amorphous silicon) having a PIN junction. Lower photoelectric conversion cell 3 (in this case, top cell), transparent intermediate layer 4 made of a light-transmitting and light-reflective metal oxide, and upper photoelectric conversion cell 5 made of crystalline Si having a PIN junction (in this case, a bottom cell) Is a thin film silicon tandem solar cell having a plurality of power generation units in which upper electrodes 6 made of a metal material such as Ag are sequentially laminated. The plurality of lower electrodes 2 are separated by a lower electrode separation groove 7. In the vicinity of the lower electrode separation groove 7, a connection groove 8 having a part of the lower electrode 2 extending from an adjacent power generation unit as a bottom surface is provided with the upper photoelectric conversion cell 5, the transparent intermediate layer 4, and the lower photoelectric conversion cell 3. It is formed by removing a part of. The upper electrode 6 extends so as to contact the inner surface of the connection groove 8 and is electrically connected to the lower electrode 2 exposed on the bottom surface of the connection groove 8. The upper electrode 6 is separated from the upper electrode of the adjacent power generation unit by the upper electrode separation groove 9 in the vicinity of the connection groove 8. Adjacent power generation units are separated by a lower electrode separation groove 7 and an upper electrode separation groove 9, but the lower electrode 2 of the other power generation unit adjacent to the upper electrode 6 of one power generation unit is electrically connected to the connection groove 8. Connected in series, forming a series connection.

(Comparative Example 1)
The film thickness of the a-Si lower photoelectric conversion cell (top cell) 3 is about 300 nm, the film thickness of the transparent intermediate layer 4 is 20 nm, the film thickness of the crystalline Si upper photoelectric conversion cell (bottom cell) 5 is about 2 μm, and is transparent. An integrated tandem solar cell having the structure shown in FIG. 1 was prepared in which the intermediate layer 4 was an Al-doped ZnO film having a single film specific resistance (resistivity) of 1 × 10 ⁻² Ω · cm. The transparent intermediate layer 4 was formed by supplying only Ar gas by RF sputtering. The Al ₂ O ₃ content concentration of the sputtering target was 2 wt%. Single film specific resistance refers to specific resistance measured when only a transparent intermediate layer is formed on an insulating glass substrate.

The lower electrode separation groove 7 for separating the lower electrode (transparent electrode) 2 was formed by laser scribing. In this comparative example, a YAG laser having a wavelength of 1064 nm was used. A YVO ₄ laser with a wavelength of 532 nm was used to form the upper electrode separation groove 9 for separating the connection groove (Si separation groove) 8 and the upper electrode (Ag electrode) 6.

The power generation characteristics of the integrated tandem solar cell thus obtained are as follows: under irradiation of AM 1.5 and light intensity of 100 mW / cm ² , efficiency 5.3%, FF (form factor) 0.58, open circuit voltage per stage (Voc) 0.85V.

(Comparative Example 2)
An integrated tandem solar cell having the structure shown in FIG. 1 was prepared using an Al-doped ZnO film having a single film specific resistance of about 1 × 10 ⁻¹ Ω · cm as the transparent intermediate layer 4. Using the same sputter target as in Comparative Example 1, 0.05 vol% oxygen was added to Ar gas to form a transparent intermediate layer (film thickness 20 nm). Other materials, manufacturing conditions, and thicknesses of the respective layers were the same as those in Comparative Example 1. The power generation characteristics of the integrated tandem solar cell thus obtained were an efficiency of 6.62%, FF 0.55, and an open circuit voltage of 1.12 V per stage.

  As described above, it has been found that when the specific resistance of the transparent intermediate layer 4 is 0.1 Ω · cm or less, that is, in the conventional integrated tandem solar cell, the influence of side leakage is large. Even if the specific resistance is 0.1 Ω · cm, the cause of the large side leak is that the oxygen in the transparent intermediate layer 4 made of a transparent oxide is a-Si lower photoelectric conversion cell (top cell) 3 sandwiching the transparent intermediate layer 4 The n-type layer and the p-type layer of the crystalline Si upper photoelectric conversion cell (bottom cell) 5 are diffused to increase the carrier concentration, so that the specific resistance in the laminated state of the transparent intermediate layer 4 is higher than the specific resistance in the single film state. It was thought to be lowered. Therefore, when the specific resistance in the laminated state was evaluated, it was found that the specific resistance decreased to about 1/20 of the single film specific resistance.

(Comparative Example 3)
An integrated tandem solar cell having the structure shown in FIG. 1 was prepared using an Al-doped ZnO film having a single film resistivity of about 1 Ω · cm as the transparent intermediate layer 4. Using the same sputter target as in Comparative Example 1, 0.67 vol% oxygen was added to Ar gas to form a transparent intermediate layer (film thickness 20 nm). Other materials, manufacturing conditions, and thicknesses of the respective layers were the same as those in Comparative Example 1. The power generation characteristics of the integrated tandem solar cell thus obtained were an efficiency of 8.62%, FF 0.61, and an open circuit voltage of 1.32 V per stage.

(Comparative Example 4)
An integrated tandem solar cell having the structure shown in FIG. 1 was prepared using a Ga-doped ZnO film having a single film resistivity of 5 Ω · cm as the transparent intermediate layer 4. A transparent intermediate layer (film thickness 20 nm) was formed by adding 0.57 wt% Ga to the sputtering target and adding 0.67 vol% oxygen to Ar gas. Other materials, manufacturing conditions, and thicknesses of the respective layers were the same as those in Comparative Example 1. The power generation characteristics of the integrated tandem solar cell thus obtained were an efficiency of 9.35%, FF 0.65, and an open circuit voltage of 1.34 V per stage.

Example 1
An integrated tandem solar cell having the structure shown in FIG. 1 was prepared using a Ga-doped ZnO film having a single film resistivity of 20 Ω · cm as the transparent intermediate layer 4. Using the same sputter target as in Comparative Example 4, 5 vol% oxygen was added to Ar gas to form a transparent intermediate layer (film thickness 20 nm). Other materials, manufacturing conditions, and thicknesses of the respective layers were the same as those in Comparative Example 1. The power generation characteristics of the integrated tandem solar cell thus obtained were an efficiency of 9.54%, FF 0.66, and an open circuit voltage of 1.35 V per stage.

(Example 2)
An integrated tandem solar cell having the structure shown in FIG. 1 was prepared using a Ga-doped ZnO film having a single film resistivity of 100 Ω · cm as the transparent intermediate layer 4. Using the same sputter target as in Comparative Example 4, 10 vol% oxygen was added to Ar gas to form a transparent intermediate layer (film thickness 20 nm). Other materials, manufacturing conditions, and thicknesses of the respective layers were the same as those in Comparative Example 1. The power generation characteristics of the integrated tandem solar cell thus obtained were an efficiency of 9.59%, FF 0.66, and an open circuit voltage of 1.35 V per stage.

(Comparative Example 5)
An integrated tandem solar cell having the structure shown in FIG. 1 was prepared using a Ga-doped ZnO film having a single film resistivity of 200 Ω · cm as the transparent intermediate layer 4. Using the same sputter target as in Comparative Example 4, 15 vol% oxygen was added to Ar gas to form a transparent intermediate layer (film thickness 20 nm). Other materials, manufacturing conditions, and thicknesses of the respective layers were the same as those in Comparative Example 1. The power generation characteristics of the integrated tandem solar cell thus obtained are an efficiency of 8.80%, an FF of 0.615, an open circuit voltage of 1.33 V per stage, and a single film specific resistance of the transparent intermediate layer 4 of 100 Ω · cm. The efficiency was lower than that of the integrated tandem solar cell of Example 2.

  FIG. 2 shows the relationship between the single film specific resistance of the transparent intermediate layer, the power generation efficiency, the FF, and the open circuit voltage per stage for the comparative examples and examples described above.

  In this embodiment, the super straight type structure has been described. However, the present invention can also be applied to a substrate type structure. The photoelectric conversion cell is not limited to thin film silicon, and the present invention can be applied to a solar battery using a thin film compound. Furthermore, the present invention can be applied not only to an integrated tandem solar cell in which two types of photoelectric conversion cells are bonded, but also to an integrated triple solar cell in which three types of photoelectric conversion cells are bonded.

It is sectional drawing which shows an integrated type tandem solar cell. It is a figure which shows the relationship of the single film specific resistance of a transparent intermediate | middle layer and power generation efficiency, FF, and the open circuit voltage per stage in the integrated tandem solar cell by the Example and comparative example of this invention.

1 Insulating substrate 2 Lower electrode 3 Lower photoelectric conversion cell 4 Transparent intermediate layer 5 Upper photoelectric conversion cell 6 Upper electrode 7 Lower electrode separation groove 8 Connection groove 9 Upper electrode separation groove

Claims (12)

An insulating substrate;
A plurality of power generation units,
At least one power generation unit is provided between a lower electrode provided on the insulating substrate, a plurality of photoelectric conversion cells stacked on the lower electrode, and two of the plurality of photoelectric conversion cells. A transparent intermediate layer provided on the upper electrode, and an upper electrode provided on the plurality of photoelectric conversion cells,
An integrated solar cell in which the upper electrode is in electrical contact with the lower electrode of another power generation unit adjacent thereto,
The transparent intermediate layer is an oxide,
Ri resistivity der less 20 [Omega · cm or more 100 [Omega · cm of the transparent intermediate layer,
An integrated solar cell in contact with the upper electrode without dividing the transparent intermediate layer . The lower electrode has a transparent oxide film;
The upper electrode has a metal film;
The photoelectric conversion cell in which the plurality of photoelectric conversion cells have an amorphous silicon film having a PIN junction, and a crystalline silicon film having a PIN junction located above the photoelectric conversion cell having the amorphous silicon film A photoelectric conversion cell comprising
The integrated solar cell according to claim 1 . The at least one power generation unit electrically connects a lower electrode separation part that separates the lower electrode from a lower electrode of another power generation unit adjacent to the lower electrode, and a lower electrode of another power generation unit adjacent to the upper electrode. And at least one power generation unit and the adjacent other power generation unit are connected in series with each other and an upper electrode separation portion that separates an upper electrode of the other power generation unit adjacent to the upper electrode. The integrated solar cell according to claim 1 or 2 . The lower electrode separation part is a lower electrode separation groove formed by removing a part of a lower electrode layer formed in common to the plurality of power generation units;
The plurality of power generation units so that the connection part separates the plurality of photoelectric conversion cells and the transparent intermediate layer of the at least one power generation unit from the plurality of photoelectric conversion cells and the transparent intermediate layer of the other adjacent power generation unit. A connection groove formed by removing a part of a laminated film having a plurality of layers for photoelectric conversion cells and a layer for a transparent intermediate layer formed in common in the unit, and extending to the connection groove A part of the upper electrode, and a part of the lower electrode of the other adjacent power generation unit that extends in the connection groove and is electrically connected to the part of the upper electrode,
The upper electrode separation part is an upper electrode separation groove formed by removing a part of the upper electrode layer formed in common to the plurality of power generation units.
The integrated solar cell according to claim 3 . The transparent intermediate layer is made of zinc oxide (ZnO), tin oxide (SnO ₂ ), indium tin oxide (ITO), copper aluminum oxide (CuAlO ₂ ), titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), oxide The integration according to any one of claims 1 to 4 , comprising at least one selected from the group consisting of zirconium (ZrO ₂ ), aluminum oxide (Al ₂ O ₃ ), and gallium oxide (Ga ₂ O ₃ ). Type solar cell. The integrated solar cell according to any one of claims 1 to 5 , wherein the plurality of photoelectric conversion cells are two photoelectric conversion cells. The integrated solar cell according to any one of claims 1 to 5 , wherein the plurality of photoelectric conversion cells are three photoelectric conversion cells. Forming a layer for the lower electrode on the insulating substrate;
Removing a part of the lower electrode layer to form a lower electrode separation groove, and forming a plurality of lower electrodes separated by the lower electrode separation groove;
A laminated body including a plurality of layers for photoelectric conversion cells and a layer for a transparent intermediate layer interposed between two of the plurality of layers is formed on the plurality of lower electrodes and the lower electrode separation grooves. And a process of
In the vicinity of the lower electrode separation groove, a part of the stacked body is removed to form a connection groove, which is separated by the connection groove, each of which is a plurality of photoelectric conversion cells and two of the plurality of photoelectric conversion cells Forming a plurality of laminated films each having a transparent intermediate layer provided between two photoelectric conversion cells on each of the plurality of lower electrodes, the bottom of the connection groove, A step of exposing a portion;
Forming a layer for an upper electrode on the plurality of laminated films, the connection groove, and the exposed lower electrode;
An upper electrode separation groove is formed by removing a part of the upper electrode layer in the vicinity of the connection groove and above the lower electrode partially exposed in the connection groove. Forming a plurality of upper electrodes separated by grooves on the plurality of stacked films, respectively, and a method of manufacturing an integrated solar cell,
Forming a layer for the transparent intermediate layer with a transparent oxide material having a specific resistance of 20 Ω · cm to 100 Ω · cm ,
The manufacturing method of the integrated solar cell which does not include the process which divides | segments the layer for said transparent intermediate | middle layers in the process of forming the said laminated body . The lower electrode layer is formed using a transparent oxide;
The upper electrode layer is formed using a metal material,
Claim 8 in which a plurality of layers for the photoelectric conversion cell includes a layer of amorphous silicon having a PIN junction, and a layer of crystalline silicon having a PIN junction positioned above the layer of amorphous silicon Manufacturing method of the integrated solar cell. The transparent material is zinc oxide (ZnO), tin oxide (SnO ₂ ), indium tin oxide (ITO), copper aluminum oxide (CuAlO ₂ ), titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), zirconium oxide ( The method for producing an integrated solar cell according to claim 8 or 9 , comprising at least one selected from the group consisting of ZrO ₂ ), aluminum oxide (Al ₂ O ₃ ), and gallium oxide (Ga ₂ O ₃ ). The method for manufacturing an integrated solar cell according to any one of claims 8 to 10 , wherein two layers for the photoelectric conversion cell are formed. The method for manufacturing an integrated solar cell according to any one of claims 8 to 10 , wherein three layers for the photoelectric conversion cell are formed.

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