JP2012114292A - Thin film photoelectric conversion device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquire a thin film photoelectric conversion device which prevents occurrence of current leakage to a connection part between a back electrode layer and a transparent electrode layer and which can be realized at low cost by a simple method, and a manufacturing method therefor.SOLUTION: In a first and a second cell adjacent to each other, a first electrode layer 102 of the first cell includes an extension part extending to the inside of a region overlapping a second electrode layer 104 of the second cell in a prescribed direction, and the second electrode layer 104 of the second cell includes a connection part which is buried penetrating a photoelectric conversion unit 103 of the second cell and which electrically connects the second electrode layer 104 on the photoelectric conversion unit 103 of the second cell and the extension part. The second cell includes a groove part 121 which is provided on a side of the connection part opposite to the first cell in a prescribed direction and which penetrates layers from a p-type semiconductor layer 103a of any photoelectric conversion unit through the first electrode layer 102, separating those layers in a prescribed direction, at least a side wall of the groove part 121 being covered with an i-type photoelectric conversion layer 103b.

Description

  The present invention relates to a structure of a thin film photoelectric conversion device and a manufacturing method thereof.

  In a conventional thin film solar cell device (thin film photoelectric conversion device), for example, a transparent electrode layer having optical transparency and a photoelectric conversion layer made of a thin film semiconductor layer are formed on a substrate on the front side, and on the back side A reflective conductive film is formed as a back electrode layer to form a thin film photovoltaic cell (thin film photoelectric conversion cell). In such a thin film photoelectric conversion cell, a photovoltaic force is generated by light incidence from the surface side (transparent electrode side).

  A plurality of thin film photoelectric conversion cells are electrically connected in series with a predetermined distance between adjacent cells to form a thin film photoelectric conversion device.

Such a thin film photoelectric conversion device is manufactured by the following method. First, a transparent insulating substrate on which a transparent electrode layer made of a transparent conductive oxide (Transparent Oxide: TCO) such as tin oxide (SnO ₂ ) or zinc oxide (ZnO) having a textured structure due to unevenness is formed on the surface. , The transparent electrode layer is processed into a stripe shape by cutting and removing a part of the transparent electrode layer by laser irradiation (laser scribing treatment) to form a separation groove. The texture structure has a function of scattering the sunlight incident on the thin film photoelectric conversion cell and increasing the light use efficiency in the thin film semiconductor layer.

  Next, a thin film semiconductor layer as a photoelectric conversion layer made of, for example, amorphous silicon is formed on the transparent electrode layer by a plasma CVD (Chemical Vapor Deposition) method or the like. Thereafter, the thin film semiconductor layer is processed into stripes by forming a separation groove by cutting and removing a part of the thin film semiconductor layer by laser irradiation at a place different from the place where the transparent electrode layer is cut.

  Next, a back electrode layer made of a light reflective metal is formed on the thin film semiconductor layer by sputtering or the like. Thereafter, the back electrode layer is processed into a stripe shape by forming a separation groove by cutting and removing a part of the back electrode layer by laser irradiation at a location different from the location where the transparent electrode layer and the thin film semiconductor layer are cut. . And in such a thin film photoelectric conversion apparatus, the high output voltage is generated by electrically connecting the thin film photoelectric conversion cells processed into stripes in series.

  In such a thin film photoelectric conversion device, a tandem structure is utilized in order to improve photoelectric conversion efficiency. The tandem structure is a thin film photoelectric conversion unit formed between a transparent electrode layer and a back electrode layer, in which a plurality of thin film photoelectric conversion units having different absorption wavelength ranges of a thin film semiconductor layer are stacked, and a wide wavelength range is obtained. In this structure, incident light can be used more effectively by absorbing the light. As an example of a tandem structure, an amorphous silicon layer having a wider band gap is used as the photoelectric conversion layer on the light incident side, and a microcrystalline silicon layer having a narrow band gap is used as the photoelectric conversion layer on the back side. The method to be used is considered.

  Moreover, in a tandem-type thin film photoelectric conversion device, an intermediate reflective layer having both light transmittance and light reflectivity and conductivity may be interposed between stacked thin film photoelectric conversion units. . The intermediate reflection layer can reflect light having a wavelength suitable for absorption by the light incident side photoelectric conversion unit out of the light that has passed through the light incident side photoelectric conversion unit. For this reason, the tandem-type thin film photoelectric conversion device has an effect that the effective film thickness of the photoelectric conversion layer of the photoelectric conversion unit on the light incident side can be increased.

  In a tandem-type thin film photoelectric conversion device having an intermediate reflective layer, the back electrode of a thin film photoelectric conversion cell and the transparent electrode layer of the thin film photoelectric conversion cell adjacent to the thin film photoelectric conversion cell must be electrically connected. is there. This electrical connection is performed by providing a separation groove penetrating the thin film photoelectric conversion unit and the intermediate reflection layer and embedding a connection electrode material in the separation groove. As the connection electrode material embedded in the separation groove, a material constituting the back electrode layer is generally used.

  However, since the adjacent thin film photoelectric conversion cells are connected by the method as described above, the connection electrode material and the intermediate reflection layer come into contact with each other. As described above, since the intermediate reflection layer has conductivity, current leakage occurs between the intermediate reflection layer on the side wall of the separation groove and the connection electrode material, and the power generated in the thin film photoelectric conversion unit cannot be effectively extracted. .

  Therefore, for example, a method of suppressing contact between the intermediate reflective layer and the connection electrode material by forming a separation groove by performing laser scribing after forming the intermediate reflective layer is considered. (For example, refer to Patent Document 1).

JP 2003-298089 A

  However, according to the technique of Patent Document 1, a new laser scribing process is added after the formation of the intermediate reflection layer, which increases the number of processing steps. For this reason, problems, such as cost increase, arise. In addition, a second thin film photoelectric conversion unit is formed after the laser scribing process. The thin film photoelectric conversion unit includes a p-type semiconductor layer, an i-type semiconductor layer (i-type photoelectric conversion layer), and an n-type semiconductor layer. Therefore, a p-type semiconductor layer is formed immediately after the laser scribing process.

  Here, the p-type semiconductor layer has high conductivity by being doped with boron (B) or the like. For this reason, although the current leakage at the side wall of the separation groove due to the conductivity of the intermediate reflection layer is suppressed by the laser scribing process, the conductive layer is formed after that, so that the current leakage is suppressed. Does not get too big. That is, since there is contact between the p-type semiconductor layer of the second thin film photoelectric conversion unit and the connection electrode material in the side wall portion of the separation groove, the effect of suppressing current leakage through the side wall of the separation groove is not so great.

  In addition, even in a single-type thin film solar cell having only one thin film photoelectric conversion unit, adjacent thin film photoelectric conversion cells are embedded by connecting electrode materials embedded in separation grooves that penetrate the thin film photoelectric conversion unit and reach the transparent electrode layer. The back electrode and the transparent electrode layer are electrically connected. Also in this case, current leakage occurs because there is contact between the p-type semiconductor layer of the thin film photoelectric conversion unit and the connection electrode material in the side wall portion of the separation groove.

  The present invention has been made in view of the above, and it is possible to prevent current leakage from occurring in a connection portion between a back electrode layer and a transparent electrode layer, and to realize a thin film photoelectric conversion device that can be realized at low cost by a simple method. It aims at obtaining a manufacturing method.

  In order to solve the above-described problems and achieve the object, a photoelectric conversion device according to the present invention includes a light-transmitting first electrode layer, a p-type semiconductor layer, and an i-type photoelectric conversion on a light-transmitting insulating substrate. A plurality of photoelectric conversion cells having one layer and an n-type semiconductor layer in this order to perform photoelectric conversion and a plurality of photoelectric conversion cells having a second electrode layer in this order are arranged in parallel in a predetermined direction. The adjacent photoelectric conversion cells are electrically connected in series, and in the adjacent first and second photoelectric conversion cells, the first electrode of the first photoelectric conversion cell The layer has an extending portion that extends into a region overlapping with the second electrode layer of the second photoelectric conversion cell in the predetermined direction, and the second electrode layer of the second photoelectric conversion cell includes: Embedded through the photoelectric conversion unit of the second photoelectric conversion cell. And having a connection part for electrically connecting the second electrode layer on the photoelectric conversion unit of the second photoelectric conversion cell and the extension part, and the second photoelectric conversion cell And passing through each layer from the p-type semiconductor layer to the first electrode layer of any one of the photoelectric conversion units provided on the opposite side of the connection portion to the first photoelectric conversion cell in the direction. It has the groove part isolate | separated in a direction, and the side wall of the said groove part is covered with the said i-type photoelectric converting layer, It is characterized by the above-mentioned.

  According to the present invention, there is an effect that a thin film photoelectric conversion device in which occurrence of current leakage of photoelectric conversion current through the side wall of the connection portion between adjacent photoelectric conversion cells is suppressed can be obtained.

FIG. 1-1 is a plan view showing a configuration of a thin-film solar battery module that is a thin-film photoelectric conversion device according to a first embodiment of the present invention. 1-2 is principal part sectional drawing explaining the cross-sectional structure in the transversal direction of the thin film photovoltaic cell which is a thin film photoelectric conversion cell which comprises the module concerning Embodiment 1 of this invention. FIG. 2 is a flowchart for explaining the module manufacturing method according to the first exemplary embodiment of the present invention. FIGS. 3-1 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 1 of this invention. FIGS. FIGS. 3-2 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 1 of this invention. FIGS. FIGS. 3-3 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 1 of this invention. FIGS. 3-4 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 1 of this invention. 3-5 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 1 of this invention. FIGS. 3-6 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 1 of this invention. FIGS. FIGS. 3-7 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 1 of this invention. FIGS. FIG. 4: is sectional drawing which shows the structure of the thin film solar cell module which is a thin film photoelectric conversion apparatus concerning Embodiment 2 of this invention. FIGS. 5-1 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 2 of this invention. FIGS. FIGS. 5-2 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 2 of this invention. FIGS. FIGS. 5-3 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 2 of this invention. FIGS. FIG. 6: is sectional drawing which shows the structure of the tandem-type thin film solar cell module which is a thin film photoelectric conversion apparatus concerning Embodiment 3 of this invention. FIGS. 7-1 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 3 of this invention. FIGS. 7-2 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 3 of this invention. FIGS. 7-3 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 3 of this invention. FIGS. 7-4 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 3 of this invention. FIGS. 7-5 is sectional drawing for demonstrating the manufacturing method of the module concerning Embodiment 3 of this invention. FIGS. FIG. 8: is sectional drawing which shows the structure of the modification of the module concerning Embodiment 3 of this invention. FIG. 9: is sectional drawing which shows the structure of the modification of the module concerning Embodiment 3 of this invention.

  Embodiments of a thin film photoelectric conversion device and a method for manufacturing the same according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited to the following description, In the range which does not deviate from the summary of this invention, it can change suitably. In the drawings shown below, the scale of each member may be different from the actual scale for easy understanding. The same applies between the drawings.

Embodiment 1 FIG.
FIG. 1-1 is a plan view illustrating a configuration of a thin film solar cell module (hereinafter referred to as a module) 10 which is a thin film photoelectric conversion device according to a first embodiment of the present invention. FIG. 1-2 is a diagram for explaining a cross-sectional structure in a short direction of a thin film photovoltaic cell (hereinafter sometimes referred to as a cell) C1, which is a thin film photoelectric conversion cell constituting the module 10, and FIG. It is principal part sectional drawing in line segment AA 'of -1.

  As illustrated in FIGS. 1-1 and 1-2, the module 10 according to the first embodiment includes a plurality of strip-like (rectangular) cells C1 formed on a light-transmissive insulating substrate 101. The cell C1 has a structure electrically connected in series. As shown in FIG. 1-2, the cell C1 includes a transparent electrode layer 102 serving as a first electrode layer, a first photoelectric conversion unit 103, and a back electrode layer 104 serving as a second electrode layer on a translucent insulating substrate 101. They are stacked in this order.

  As the light-transmitting insulating substrate 101, a light-transmitting insulating substrate is used. For such a translucent insulating substrate 101, a material having a high light transmittance is usually used, and for example, a glass substrate is used. As the glass substrate, an alkali-free glass substrate may be used, or an inexpensive blue plate glass substrate may be used. However, the light-transmitting insulating substrate 101 is not necessarily made of glass, and a substrate such as a resin can be used as long as it is an insulating substrate that transmits light.

The transparent electrode layer 102 is made of a transparent conductive film having translucency. In two adjacent cells C1, the transparent electrode layer 102 of one cell C1 has an extending portion that extends to a region overlapping with the back electrode layer 104 of the other cell C1, and straddles the other cell C1. Is formed. The transparent electrode layer 102 is, for example, a transparent conductive material containing at least one of zinc oxide (ZnO), indium tin oxide (ITO), tin oxide (SnO ₂ ), and indium oxide (In ₂ O ₃ ). It is composed of an oxide film (TCO: Transparent Conducting Oxide) or a transparent conductive film in which these are laminated. In addition, the transparent electrode layer 102 is formed by using aluminum (Al), gallium (Ga), indium (In), boron (B), yttrium (Y), silicon (Si), zirconium (Zr), You may be comprised by the translucent film | membrane using at least 1 or more types of element selected from titanium (Ti) and fluorine (F). Such a transparent electrode layer 102 is formed using methods, such as CVD method, sputtering method, a vapor deposition method, for example.

  Further, the transparent electrode layer 102 has a surface texture structure in which an uneven shape (not shown) is formed on the surface on the first photoelectric conversion unit 103 side. This texture structure has a function to scatter incident sunlight, absorb incident light more efficiently by the first photoelectric conversion unit 103, and improve light utilization efficiency. The formation method of a surface texture structure is not specifically limited, A well-known method can be used.

  The first photoelectric conversion unit 103 has a pn junction or a pin junction, and is configured by stacking one or more thin film semiconductor layers that generate power by incident light. As shown in FIG. 1-2, the first photoelectric conversion unit 103 includes a p-type semiconductor layer 103a, an i-type (intrinsic) photoelectric conversion layer 103b, and an n-type semiconductor layer 103c from the transparent electrode layer 102 side. Here, the p-type semiconductor layer 103a has conductivity, but the i-type (intrinsic) photoelectric conversion layer 103b does not have conductivity. In the present embodiment, the first photoelectric conversion unit 103 has a structure in which a p-type silicon semiconductor layer, an i-type amorphous silicon photoelectric conversion layer, and an n-type silicon semiconductor layer are stacked from the transparent electrode layer 102 side. Yes. Such a first photoelectric conversion unit 103 can be formed using, for example, a plasma CVD method.

  In this embodiment, an i-type amorphous silicon photoelectric conversion layer is used as the i-type photoelectric conversion layer 103b in the first photoelectric conversion unit 103. However, the i-type photoelectric conversion layer 103b is an i-type amorphous silicon-based layer. It may be formed of a semiconductor material, and an alloy such as silicon germanium (SiGe) or silicon carbide (SiC) may be used in addition to intrinsic silicon. The p-type semiconductor layer 103a is required to have high conductivity and high light transmittance. For example, silicon carbide (SiC) to which boron (B) or the like is added is used.

  The back electrode layer 104 functions as a back electrode and also functions as a reflective layer that reflects light that has not been absorbed by the photoelectric conversion layer and returns the light back to the photoelectric conversion layer, thereby contributing to improvement in photoelectric conversion efficiency. Therefore, the back electrode layer 104 is required to have conductivity and light reflectivity, and it is preferable that the conductivity is high and the light reflectivity is large. The back electrode layer 104 is formed of a metal material such as silver (Ag), aluminum (Al), titanium (Ti), or palladium having a high visible light reflectance, or an alloy of these metal materials, a nitride of these metal materials, These metal materials can be used to form oxides. In addition, the specific material of these back surface electrode layers 104 is not specifically limited, It can select from a well-known material suitably and can be used. Further, the back electrode layer 104 may have a stacked structure of a plurality of electrode layers in order to suppress reaction with the first photoelectric conversion unit 103, atomic diffusion, and the like.

  Moreover, in the module 10, in order to ensure a voltage required as a thin film solar cell, the cells C1 formed on the translucent insulating substrate 101 are electrically connected in series.

  The transparent electrode layer 102 and the p-type semiconductor layer 103a formed on the translucent insulating substrate 101 extend in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101 and are also transparent to the translucent insulating substrate 101. A first groove 121 which is a stripe-shaped separation groove reaching the distance is formed. The first groove 121 is formed over the entire width in the longitudinal direction of the cell C1. The transparent electrode layers 102 of the adjacent cells C1 are separated from each other by the portion of the first groove 121. In this way, a part of the transparent electrode layer 102 is separated for each cell so as to straddle the adjacent cell C1. An i-type photoelectric conversion layer 103 b having no conductivity is embedded in the first groove 121. An i-type photoelectric conversion layer 103b is formed on the portion of the first groove 121 in which the i-type photoelectric conversion layer 103b is embedded and on the p-type semiconductor layer 103a.

  Further, the first photoelectric conversion unit 103 formed on the transparent electrode layer 102 extends in a direction substantially parallel to the transversal insulating substrate 101 at a location different from the first groove 121 and is transparent. A second groove 122 that is a stripe-shaped connection groove reaching the electrode layer 102 is formed. The back electrode layer 104 is connected to the transparent electrode layer 102 by embedding the back electrode layer 104 in the portion of the second groove 122. And since this transparent electrode layer 102 straddles the adjacent cell C1, one back electrode layer 104 and the other transparent electrode layer 102 of two adjacent cells C1 are electrically connected. That is, the back electrode layer 104 has a connection portion embedded in the second groove 122. Further, the connection portion may be formed on at least the side wall of the second groove 122 and electrically connected to the transparent electrode layer 102 of the other cell C1. The second groove 122 may not be formed over the entire width in the longitudinal direction of the cell C1.

  Further, in the back electrode layer 104 and the first photoelectric conversion unit 103, a third groove which is a stripe-shaped separation groove reaching the transparent electrode layer 102 at a location different from the first groove 121 and the second groove 122. 123 is formed, and each cell C1 is separated. In this way, the transparent electrode layer 102 of the cell C1 is connected to the back electrode layer 104 of the adjacent cell C1, so that the adjacent cells C1 are electrically connected in series. Note that the third groove 123 preferably reaches the transparent electrode layer 102 from the surface of the back electrode layer 104 to separate the first photoelectric conversion unit 103 for each cell, but only the back electrode layer 104 is the third electrode. It is also possible to adopt a form separated by the grooves 123.

  Next, a manufacturing method of the module 10 according to the present embodiment configured as described above will be described with reference to FIG. 2 and FIGS. 3-1 to 3-7. FIG. 2 is a flowchart for explaining a manufacturing method of the module 10 according to the first embodiment. 3-1 to 3-7 are cross-sectional views for explaining the method for manufacturing the module 10 according to the first embodiment.

  First, for example, a glass substrate is prepared as the translucent insulating substrate 101. And the transparent electrode layer 102 with high electroconductivity is formed in the one surface side of the translucent insulated substrate 101 by a well-known method (step S10, FIG. 3-1). For example, the transparent electrode layer 102 made of a zinc oxide (ZnO) film is formed over the light-transmitting insulating substrate 101 by a sputtering method. Further, as a film formation method, another film formation method such as a CVD method may be used.

  Next, the p-type semiconductor layer 103a of the first photoelectric conversion unit 103 is formed on the transparent electrode layer 102 by a known method (step S20, FIG. 3-1). For example, a p-type silicon semiconductor layer is formed on the transparent electrode layer 102 by a plasma CVD method as the p-type semiconductor layer 103a.

  Next, a part of the transparent electrode layer 102 and the p-type semiconductor layer 103a is cut and removed in a stripe shape in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101, and the transparent electrode layer 102 and the p-type semiconductor are removed. The layer 103a is patterned into a strip shape, and the transparent electrode layer 102 and the p-type semiconductor layer 103a are separated into a plurality. Patterning of the transparent electrode layer 102 and the p-type semiconductor layer 103a is performed by removing all of the transparent electrode layer 102 and the transparent electrode layer 102 from the interface (transparent electrode layer 102 side) all together by laser scribing. This is performed by forming a stripe-shaped first groove 121 extending in a direction substantially parallel to the lateral direction of the light-insulating substrate 101 and reaching the light-transmitting insulating substrate 101 (step S30, FIG. 3-2). . Note that the first groove 121 can be formed by a method such as etching using a resist mask formed by photolithography or a vapor deposition method using a metal mask.

  Next, the i-type photoelectric conversion layer 103b is formed on the p-type semiconductor layer 103a including the inside of the first groove 121 by a known method (step S40, FIG. 3-3). For example, an i-type amorphous silicon photoelectric conversion layer is formed as the i-type photoelectric conversion layer 103b by a plasma CVD method. Thereby, the i-type photoelectric conversion layer 103 b is embedded in the first groove 121.

  Next, the n-type semiconductor layer 103c is formed on the i-type photoelectric conversion layer 103b by a known method (step S50, FIG. 3-4). For example, an n-type silicon semiconductor layer is formed as the n-type semiconductor layer 103c by a plasma CVD method. Thereby, the 1st photoelectric conversion unit 103 by which the p-type semiconductor layer 103a, the i-type photoelectric conversion layer 103b, and the n-type semiconductor layer 103c were laminated | stacked from the transparent electrode layer 102 side is comprised.

  Then, patterning is performed on the first photoelectric conversion unit 103 thus laminated by laser scribing. That is, a part of the first photoelectric conversion unit 103 is cut and removed in a stripe shape in a direction substantially parallel to the short direction of the translucent insulating substrate 101, and the first photoelectric conversion unit 103 is patterned into a strip shape, The first photoelectric conversion unit 103 is separated into a plurality. The patterning of the first photoelectric conversion unit 103 is performed by removing all the upper portions (on the p-type semiconductor layer 103a side) above the interface between the transparent electrode layer 102 and the p-type semiconductor layer 103a by a laser scribe method. Is formed by forming a stripe-shaped second groove 122 extending in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101 and reaching the transparent electrode layer 102 (step S60, FIG. 3). -5). After the formation of the second groove 122, the scattered matter adhering in the second groove 122 is removed by high-pressure water cleaning, megasonic cleaning, or brush cleaning.

  Next, the back electrode layer 104 is formed on the first photoelectric conversion unit 103 including the inside of the second groove 122 by a known method (step S70, FIGS. 3-6). For example, the back electrode layer 104 made of a silver (Ag) film having a high reflectance is formed by a sputtering method. At this time, the back electrode layer 104 is also embedded in the second groove 122 and connected to the transparent electrode layer 102. As a result, the back electrode layer 104 is electrically connected to the transparent electrode layer 102 in the second groove 122. Further, as a film forming method, another film forming method such as an evaporation method may be used.

  After the back electrode layer 104 is formed, at least the back electrode layer 104 is patterned and separated into a plurality of cells C1. Here, the back electrode layer 104 and a part of the first photoelectric conversion unit 103 are cut and removed in a stripe shape in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101 and patterned into a strip shape, Separated into a plurality of cells C1. The patterning is performed by removing all the portions above the interface between the transparent electrode layer 102 and the p-type semiconductor layer 103a (on the p-type semiconductor layer 103a side) by a laser scribe method. Is performed by forming a striped third groove 123 extending in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101 and reaching the transparent electrode layer 102 at different locations (step S80, FIG. 3). -7).

  In addition, since it is difficult to directly absorb the laser in the back electrode layer 104 having a high reflectivity, the semiconductor layer (first photoelectric conversion unit 103) absorbs laser light energy, and the semiconductor layer (first photoelectric conversion unit 103). At the same time, the back electrode layer 104 is locally blown off to be separated corresponding to the plurality of cells C1. Here, the back electrode layer 104 and the third groove 123 penetrating the first photoelectric conversion unit 103 are formed. However, a separation groove is formed only in the back electrode layer 104, and the back electrode layer 104 is formed into a plurality of cells C1. May be separated. Thus, the module 10 having the cell C1 as shown in FIG. 1-2 is obtained.

  In the above description, a laser is used to form the first groove 121, the second 122, and the third 123, but these formation methods are not particularly limited. In addition, since these groove regions become ineffective regions for photoelectric conversion, it is possible to form grooves as small as possible as a method for forming these grooves, and it is preferable that the method is inexpensive.

  As described above, in the first embodiment, after the p-type semiconductor layer 103a is formed, the first groove 121 that penetrates the transparent electrode layer 102 and the p-type semiconductor layer 103a and reaches the light-transmissive insulating substrate 101 is formed. The p-type semiconductor layer 103a is divided in the cell. In the first groove 121, an i-type photoelectric conversion layer 103b having no conductivity is embedded. Thereby, the photoelectric conversion current generated in the first photoelectric conversion unit 103 is an electrical connection portion between the back electrode layer 104 and the transparent electrode layer 102 via the p-type semiconductor layer 103a on the side surface of the second groove 122. Leakage to the back electrode layer 104 embedded in the second groove 122 can be suppressed.

  In the above description, the first groove 121 is described as being filled with the i-type photoelectric conversion layer 103b in the depth direction. However, the first groove 121 is filled with the i-type photoelectric conversion layer 103b. That is not essential. The i-type photoelectric conversion layer 103b may be covered with the side surface of the transparent electrode layer 102 and the side surface of the p-type semiconductor layer 103a in the first groove 121. For example, when the transparent electrode layer 102 is thicker than the i-type photoelectric conversion layer 103b, the i-type photoelectric conversion layer 103b fills the first groove 121 only halfway in the depth direction. However, since the i-type photoelectric conversion layer 103b covers and covers the conductive transparent electrode layer 102 and the p-type semiconductor layer 103a, current leakage can be prevented from occurring through these side surfaces. The same applies to the following embodiments.

Embodiment 2. FIG.
FIG. 4: is sectional drawing which shows the structure of the thin film solar cell module 20 which is a thin film photoelectric conversion apparatus concerning Embodiment 2 of this invention. The module 20 has a planar configuration shown in FIG. FIG. 4 is a cross-sectional view of the main part in the direction of line AA ′ in FIG.

  As shown in FIG. 4, the module 20 according to the second embodiment includes a plurality of strip-shaped (rectangular) cells C2 formed on a light-transmitting insulating substrate 101, and these cells C2 are electrically connected in series. It has the structure connected to. In the cell C2, as shown in FIG. 4, a transparent electrode layer 102, a first photoelectric conversion unit 103 ', and a back electrode layer 104 are laminated in this order on a translucent insulating substrate 101. In addition, about the structure similar to the cell C1 concerning Embodiment 1, detailed description is abbreviate | omitted by attaching | subjecting the same code | symbol as Embodiment 1. FIG.

  The module 20 according to the second embodiment is different from the module 10 according to the first embodiment in that the first photoelectric conversion unit 103 ′ constituting the module is between the p-type semiconductor layer 103a and the i-type photoelectric conversion layer 103b. A non-conductive (i-type) buffer layer 111 is provided. For the buffer layer 111, for example, an amorphous silicon film or an amorphous silicon carbide film can be used.

  A method for manufacturing the module 20 according to the second embodiment configured as described above will be described with reference to FIGS. 5A to 5C are cross-sectional views for explaining the method for manufacturing the module 20 according to the second embodiment.

  First, as in the case of the first embodiment, the transparent electrode layer 102 and the p-type semiconductor layer 103a are sequentially formed on one surface side of the translucent insulating substrate 101 by a known method. Then, the buffer layer 111 is formed on the p-type semiconductor layer 103a by a plasma CVD method or the like (FIG. 5-1).

  Next, in the same manner as in the first embodiment, a stripe-shaped first extending in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101 and reaching the translucent insulating substrate 101 by a laser scribing method. The groove 121 is formed (FIG. 5-2). Thereby, the buffer layer 111, the p-type semiconductor layer 103a, and the transparent electrode layer 102 are separated into a plurality.

  Next, the i-type photoelectric conversion layer 103b is formed on the buffer layer 111 including the inside of the first groove 121 by a known method (FIG. 5-3). For example, an i-type amorphous silicon photoelectric conversion layer is formed as the i-type photoelectric conversion layer 103b by a plasma CVD method. Thereby, the i-type photoelectric conversion layer 103 b is embedded in the first groove 121.

  Thereafter, the n-type semiconductor layer 103c is formed in the same manner as in the first embodiment, the second groove 122 is formed, the back electrode layer 104 is formed, and the third groove 123 is formed. A module 20 having a cell C2 as shown in FIG. 4 is obtained.

  As described above, in the second embodiment, after the buffer layer 111 is formed, the first groove 121 that penetrates the buffer layer 111, the p-type semiconductor layer 103a, and the transparent electrode layer 102 to reach the light-transmitting insulating substrate 101 is formed. Then, the p-type semiconductor layer 103a is divided in the cell. In the first groove 121, an i-type photoelectric conversion layer 103b having no conductivity is embedded. Thereby, the photoelectric conversion current generated in the first photoelectric conversion unit 103 is a second connection portion between the back electrode layer 104 and the transparent electrode layer 102 via the p-type semiconductor layer 103a on the side surface of the second groove 122. Leakage into the back electrode layer 104 embedded in the groove 122 can be suppressed.

  In the second embodiment, the first groove 121 is formed after the buffer layer 111 is formed on the p-type semiconductor layer 103a. As a result, the oxidation of the p-type semiconductor layer 103a that occurs during the step of forming the first groove 121 can be suppressed, and the decrease in the conductivity of the p-type semiconductor layer 103a due to the oxidation can be avoided. In this case, the buffer layer 111 is preferably an oxide layer made of a silicon oxide film (SiO film) or the like, and has a high photoconductivity and a large band gap such as a microcrystalline silicon oxide film (μc-SiO film). Is more preferable. By using the buffer layer 111 made of an oxide film, even when the outermost surface of the buffer layer 111 is naturally oxidized when the first groove 121 is formed, the influence on the film characteristics and the interface portion can be reduced. it can. Furthermore, by using an oxide film having a wide band gap as the buffer layer 111, the open-circuit voltage (Voc) can be improved.

Embodiment 3 FIG.
FIG. 6: is sectional drawing which shows the structure of the tandem-type thin film solar cell module 30 which is a thin film photoelectric conversion apparatus concerning Embodiment 3 of this invention. The module 30 has a planar configuration shown in FIG. FIG. 6 is a cross-sectional view of the main part in the direction of the line AA ′ in FIG.

  As shown in FIG. 6, the module 30 according to the third embodiment includes a plurality of strip-shaped (rectangular) cells C3 formed on the translucent insulating substrate 101, and these cells C3 are electrically connected in series. It has the structure connected to. As shown in FIG. 6, the cell C3 includes a transparent electrode layer 102, a first photoelectric conversion unit 103, an intermediate reflection layer 112, a second photoelectric conversion unit 105, and a back electrode layer 104 in this order on a translucent insulating substrate 101. Are stacked. In addition, about the structure similar to the cell C1 concerning Embodiment 1, detailed description is abbreviate | omitted by attaching | subjecting the same code | symbol as Embodiment 1. FIG.

  The module 30 according to the third embodiment is different from the module 10 according to the first embodiment in that the intermediate reflection layer 112 and the second photoelectric conversion unit 105 are provided between the first photoelectric conversion unit 103 and the back electrode layer 104. Is to have.

  The second photoelectric conversion unit 105 has a pn junction or a pin junction, and is configured by laminating one or more thin film semiconductor layers that generate power with incident light. As shown in FIG. 6, the second photoelectric conversion unit 105 includes a p-type semiconductor layer 105a, an i-type (intrinsic) photoelectric conversion layer 105b, and an n-type semiconductor layer 105c from the intermediate reflection layer 112 side. Here, the p-type semiconductor layer 105a has conductivity, but the i-type (intrinsic) photoelectric conversion layer 105b does not have conductivity. In the present embodiment, the second photoelectric conversion unit 105 has a structure in which a p-type silicon semiconductor layer, an i-type microcrystalline silicon photoelectric conversion layer, and an n-type silicon semiconductor layer are stacked from the intermediate reflection layer 112 side. . Such a second photoelectric conversion unit 105 can be formed using, for example, a plasma CVD method.

  In the module 30, an i-type amorphous silicon photoelectric conversion layer is used as the photoelectric conversion layer in the first photoelectric conversion unit 103, and an i-type microcrystalline silicon photoelectric conversion layer is used as the photoelectric conversion layer in the second photoelectric conversion unit 105. Is used. The i-type amorphous silicon photoelectric conversion layer and the i-type microcrystalline silicon photoelectric conversion layer have different wavelength ranges of light to be absorbed. For example, the amorphous silicon photoelectric conversion layer efficiently absorbs light having a wavelength of about 550 nm, and the microcrystalline silicon photoelectric conversion layer efficiently absorbs light having a wavelength of about 900 nm. Therefore, by laminating a plurality of photoelectric conversion units having different wavelength ranges of light to be absorbed, light in a wide wavelength range can be effectively used to improve photoelectric conversion efficiency.

  The intermediate reflection layer 112 has both light transmission properties and light reflection properties, and has conductivity so as not to prevent electrical connection between the first photoelectric conversion unit 103 and the second photoelectric conversion unit 105. . The intermediate reflection layer 112 can reflect light having a wavelength that is absorbed by the first photoelectric conversion unit 103 out of the light that has passed through the first photoelectric conversion unit 103 on the light incident side, and the second photoelectric conversion layer 105b Absorbing wavelength light can be transmitted. The intermediate reflection layer 112 has such an effect that the effective film thickness of the photoelectric conversion layer of the first photoelectric conversion unit 103 can be increased.

For the intermediate reflective layer 112, for example, a transparent conductive oxide film such as tin oxide (SnO ₂ ), titanium oxide (TiO ₂ ), or silicon oxide (SiO ₂ ) can be used. The intermediate reflective layer 112 is not limited to these materials, and materials other than the oxide film can be used as long as they have conductivity and the above optical characteristics. The formation of the intermediate reflection layer 112 is not indispensable, and may not be formed if unnecessary.

  A method of manufacturing the module 30 according to the third embodiment configured as described above will be described with reference to FIGS. 7-1 to 7-5. 7A to 7E are cross-sectional views for explaining a method for manufacturing the module 30 according to the third embodiment.

  First, the transparent electrode layer 102, the p-type semiconductor layer 103a, the i-type photoelectric conversion layer 103b, the n-type semiconductor layer 103c, the intermediate reflection layer 112, and the p-type semiconductor layer 105a are formed on one surface side of the translucent insulating substrate 101 by plasma, for example. It forms in order on the transparent electrode layer 102 using CVD method (FIGS. 7-1).

  Next, stripe-shaped first grooves 121 extending in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101 and reaching the translucent insulating substrate 101 are formed by laser scribing (FIG. 7). -2). Thereby, the transparent electrode layer 102, the p-type semiconductor layer 103a, the i-type photoelectric conversion layer 103b, the n-type semiconductor layer 103c, the intermediate reflection layer 112, and the p-type semiconductor layer 105a are separated into a plurality of layers.

Here, since the p-type semiconductor layer 105a is formed on the intermediate reflective layer 112 when the first groove 121 is formed, the influence of oxidation of the intermediate reflective layer 112 when the first groove 121 is formed is suppressed. be able to. Conventionally, a transparent conductive oxide film such as tin oxide (SnO ₂ ), titanium oxide (TiO ₂ ), or silicon oxide (SiO ₂ ) has been used for the intermediate reflective layer 112. However, in this embodiment, since the p-type semiconductor layer 105a can suppress the influence of oxidation or the like of the intermediate reflection layer 112 when the first groove 121 is formed, the p-type semiconductor layer 105a has conductivity and the above optical characteristics. Any material other than the oxide film can be used for the intermediate reflective layer 112 as long as it has the characteristics, and there is an effect that the selection range of materials is widened.

  Next, the i-type photoelectric conversion layer 105b and the n-type semiconductor layer 105c are sequentially formed by a known method on the p-type semiconductor layer 105a including the inside of the first groove 121 (FIG. 7-3). For example, an i-type amorphous silicon photoelectric conversion layer is formed as the i-type photoelectric conversion layer 105b by a plasma CVD method. Thereby, the i-type photoelectric conversion layer 105 b is embedded in the first groove 121. Further, an n-type silicon semiconductor layer is formed as the n-type semiconductor layer 105c by a plasma CVD method.

  Next, a stripe-shaped second groove 122 extending in a direction substantially parallel to the transversal direction of the translucent insulating substrate 101 and reaching the transparent electrode layer 102 is formed by a laser scribing method (FIG. 7-4). ). Thereby, the p-type semiconductor layer 103a, the i-type photoelectric conversion layer 103b, the n-type semiconductor layer 103c, the intermediate reflection layer 112, the p-type semiconductor layer 105a, the i-type photoelectric conversion layer 105b, and the n-type semiconductor layer 105c have a plurality of layers. To be separated.

  Thereafter, the back electrode layer 104 is formed in the same manner as in the first embodiment, and the third groove 123 is formed, whereby the module 30 having the cell C3 as shown in FIG. 6 is obtained.

  As described above, in the third embodiment, after the p-type semiconductor layer 105a of the second photoelectric conversion unit 105 is formed, the transparent electrode layer 102, the p-type semiconductor layer 103a, the i-type photoelectric conversion layer 103b, and the n-type semiconductor layer 103c. The first groove 121 is formed so as to penetrate the intermediate reflective layer 112 and the p-type semiconductor layer 105a and reach the light-transmissive insulating substrate 101, and the p-type semiconductor layer 103a, the intermediate reflective layer 112, and the p-type semiconductor layer 105a are formed in the cell. Divided within. Then, an i-type photoelectric conversion layer 105 b having no conductivity is embedded in the first groove 121.

  Thereby, the photoelectric conversion current generated in the first photoelectric conversion unit 103 is a second connection portion between the back electrode layer 104 and the transparent electrode layer 102 via the p-type semiconductor layer 103a on the side surface of the second groove 122. Leakage into the back electrode layer 104 embedded in the groove 122 can be suppressed. In addition, the photoelectric conversion current generated in the second photoelectric conversion unit 105 leaks to the back electrode layer 104 embedded in the second groove 122 via the p-type semiconductor layer 105 a on the side surface of the second groove 122. Can be suppressed. In addition, the back surface in which the photoelectric conversion current flowing between the first photoelectric conversion unit 103 and the second photoelectric conversion unit 105 is embedded in the second groove 122 on the side surface of the second groove 122 via the intermediate reflection layer 112. Leakage into the electrode layer 104 can be suppressed.

  In the case of a tandem-type thin-film solar cell in which two photoelectric conversion units are stacked via an intermediate reflection layer as in the module 30 according to the present embodiment, the first photoelectric conversion unit as shown in the first embodiment. Even when the first groove 121 is formed after the p-type semiconductor layer 103a of 103 is formed and the i-type photoelectric conversion layer 103b is embedded in the first groove 121, the transparent electrode layer is conventionally formed. Suppressing the generation of leakage current to the back electrode layer 104 embedded in the second groove 122, compared to the case where the first groove is formed after forming the 102 and the p-type semiconductor layer is embedded in the groove. The effect is obtained. However, in this case, a leakage current is generated on the side surface of the second groove 122 via the intermediate reflective layer 112 and the p-type semiconductor layer 105a, so that leakage to the back electrode layer 104 embedded in the second groove 122 occurs. The effect of suppressing current generation is not so great.

  Therefore, after forming the p-type semiconductor layer 105a of the second photoelectric conversion unit 105, which is the uppermost photoelectric conversion unit in contact with the back electrode layer 104, the first groove 121 is formed, and the first groove 121 is formed in the first groove 121. By embedding the i-type photoelectric conversion layer 105b, since the conductive film that causes leakage is not embedded in the first groove 121, the effect of suppressing the generation of leakage current is maximized. That is, after forming the p-type semiconductor layer of the uppermost photoelectric conversion unit in contact with the back electrode layer 104, the first groove 121 is formed and the i-type photoelectric conversion layer is embedded in the first groove 121. Therefore, since the conductive film that causes leakage is not embedded in the first groove 121, the effect of suppressing generation of leakage current is increased.

  In the third embodiment, since the intermediate reflective layer 112 is separated in the cell when the first groove 121 is formed, an independent process for separating the intermediate reflective layer 112 is unnecessary, and the number of processes is increased. The generation of leakage current by the intermediate reflection layer 112 can be suppressed without any problems.

  The module 30 has a configuration in which two photoelectric conversion units of the first photoelectric conversion unit 103 and the second photoelectric conversion unit 105 are stacked, but the number of stacked photoelectric conversion units is not limited to this, that is, A stacked structure in which three or more photoelectric conversion units are stacked may be employed.

  FIG. 8 is a cross-sectional view illustrating a configuration of a module 40 that is a modification of the module 30. The module 40 has a planar configuration shown in FIG. FIG. 8 is a cross-sectional view of the main part in the direction of the line A-A ′ in FIG. As shown in FIG. 8, the module 40 includes a plurality of strip-shaped (rectangular) cells C4 formed on the light-transmitting insulating substrate 101, and the cells C4 are electrically connected in series. Have. In addition, about the structure similar to said embodiment, detailed description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  The cell C4 includes a second photoelectric conversion unit 105 'in which the buffer layer 111 is applied to the second photoelectric conversion unit 105 in the configuration of the cell C3. That is, the module 40 is formed by a method of forming the buffer layer 111 made of an oxide film immediately before forming the first groove 121, as in the case of the second embodiment. Thereby, the oxidation of the p-type semiconductor layer 105a generated during the process of forming the first groove 121 can be suppressed, and the decrease in the conductivity of the p-type semiconductor layer 105a due to the oxidation can be avoided.

  FIG. 9 is a cross-sectional view illustrating a configuration of a module 50 that is a modification of the module 30. The module 50 has a planar configuration shown in FIG. FIG. 9 is a cross-sectional view of the main part in the direction of line A-A ′ in FIG. As shown in FIG. 9, the module 50 includes a plurality of strip-shaped (rectangular) cells C5 formed on a light-transmitting insulating substrate 101, and the cells C5 are electrically connected in series. Have. In addition, about the structure similar to said embodiment, detailed description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  The cell C5 has a configuration in which the intermediate reflection layer 113 and the third photoelectric conversion unit 106 are inserted on the rear stage side of the second photoelectric conversion unit 105 in the cell C3. The intermediate reflection layer 113 is both light transmissive and light reflective like the intermediate reflection layer 112, and is conductive. The third photoelectric conversion unit 106 has a pn junction or a pin junction, and is configured by stacking one or more thin film semiconductor layers that generate power by incident light. As shown in FIG. 9, the third photoelectric conversion unit 106 includes a p-type semiconductor layer 106a, an i-type (intrinsic) photoelectric conversion layer 106b, and an n-type semiconductor layer 106c from the intermediate reflection layer 113 side. Here, the p-type semiconductor layer 106a has conductivity, but the i-type (intrinsic) photoelectric conversion layer 106b does not have conductivity.

  In the module 50, an i-type photoelectric conversion layer 106 b that is an i-type (intrinsic) photoelectric conversion layer having no conductivity is embedded in the first groove 121. That is, after forming the p-type semiconductor layer 106a of the third photoelectric conversion unit 106, which is the uppermost photoelectric conversion unit in contact with the back electrode layer 104, the first groove 121 is formed, and the first groove 121 is formed in the first groove 121. By embedding the i-type photoelectric conversion layer 106b, a conductive film that causes leakage is not embedded in the first groove 121, so that a favorable effect of suppressing leakage current generation can be obtained.

  As described in the above-described embodiment, in the case of a single-type thin film solar cell, the transparent electrode layer 102 and the p-type semiconductor layer of the photoelectric conversion unit are collectively removed to form the first groove 121, An i-type photoelectric conversion layer of the photoelectric conversion unit is embedded in the first groove 121. Thus, the photoelectric conversion efficiency can be reduced by suppressing the photoelectric conversion current from leaking to the back electrode layer 104 embedded in the second groove 122 via the side wall of the second groove 122 at a low cost by a simple method. Can be improved.

  Further, in the case of a stacked thin film solar cell in which two stages of photoelectric conversion units from the light incident side (front and rear stages from the light incident side) are stacked, the transparent electrode layer 102 and all layers of the preceding photoelectric conversion unit A part and a part of the p-type semiconductor layer of the subsequent photoelectric conversion unit are collectively removed to form the first groove 121, and the i-type photoelectric conversion layer of the subsequent photoelectric conversion unit is formed in the first groove 121. Buried. Thus, the photoelectric conversion efficiency can be reduced by suppressing the photoelectric conversion current from leaking to the back electrode layer 104 embedded in the second groove 122 via the side wall of the second groove 122 at a low cost by a simple method. Can be improved.

  In the case of a stacked thin film solar cell having three stages of photoelectric conversion units (front, middle, and rear from the light incident side), after the formation of the p-type semiconductor layer of the subsequent photoelectric conversion unit, the subsequent photoelectric conversion is performed. Part of each layer from the p-type semiconductor layer of the unit to the transparent electrode layer 102 is collectively removed to form a first groove 121, and the i-type photoelectric conversion layer of the subsequent photoelectric conversion unit is formed in the first groove 121. Is buried. In addition, after the formation of the p-type semiconductor layer of the middle photoelectric conversion unit, a part of each layer from the p-type semiconductor layer to the transparent electrode layer 102 of the middle photoelectric conversion unit is collectively removed to form the first groove 121. In the first groove 121, an i-type photoelectric conversion layer of a middle-stage photoelectric conversion unit may be embedded. Thus, the photoelectric conversion efficiency can be reduced by suppressing the photoelectric conversion current from leaking to the back electrode layer 104 embedded in the second groove 122 via the side wall of the second groove 122 at a low cost by a simple method. Can be improved.

  In addition, when the photoelectric conversion layer in the photoelectric conversion unit on the uppermost layer (on the back electrode layer 104 side) is formed of microcrystalline silicon, the photoelectric conversion layer in the portion embedded in the groove 121 is affected by the base and shape. As a result, film quality such as crystallization rate deteriorates. For this reason, the conductivity is lowered even during light irradiation, and the effect of suppressing the occurrence of leakage current is enhanced.

  As described above, the thin film photoelectric conversion device according to the present invention is useful when a thin film photoelectric conversion device in which the occurrence of current leakage through the side wall of the separation groove is prevented is realized by a simple method at low cost.

10, 20, 30, 40, 50 Thin film solar cell module (module)
DESCRIPTION OF SYMBOLS 101 Translucent insulating substrate 102 Transparent electrode layer 103, 103 'Photoelectric conversion unit 103a p-type semiconductor layer 103b i-type (intrinsic) photoelectric conversion layer 103c n-type semiconductor layer 104 Back surface electrode layer 105, 105' Photoelectric conversion unit 105a p-type Semiconductor layer 105b i-type (intrinsic) photoelectric conversion layer 105c n-type semiconductor layer 106 photoelectric conversion unit 106a p-type semiconductor layer 106b i-type (intrinsic) photoelectric conversion layer 106c n-type semiconductor layer 111 buffer layer 112, 113 intermediate reflection layer 121 first 1 groove 122 2nd groove 123 3rd groove C1, C2, C3, C4, C5 Thin film photovoltaic cell (cell)

Claims (9)

One or more photoelectric elements that perform photoelectric conversion by having a light-transmitting first electrode layer, a p-type semiconductor layer, an i-type photoelectric conversion layer, and an n-type semiconductor layer in this order on a light-transmitting insulating substrate. A thin film photoelectric conversion device in which a plurality of photoelectric conversion cells having a conversion unit and a second electrode layer in this order are arranged in parallel in a predetermined direction, and the adjacent photoelectric conversion cells are electrically connected in series. There,
In the adjacent first and second photoelectric conversion cells,
The first electrode layer of the first photoelectric conversion cell has an extending portion that extends to a region overlapping with the second electrode layer of the second photoelectric conversion cell in the predetermined direction,
The second electrode layer of the second photoelectric conversion cell is embedded through the photoelectric conversion unit of the second photoelectric conversion cell and the second electrode on the photoelectric conversion unit of the second photoelectric conversion cell. A connecting portion for electrically connecting the layer and the extending portion;
The second photoelectric conversion cell is provided on the opposite side of the connection portion from the first photoelectric conversion cell in the predetermined direction, and extends from the p-type semiconductor layer of any one of the photoelectric conversion units to the first electrode layer. Having a groove portion that penetrates each layer and separates each layer in the predetermined direction, and at least a sidewall of the groove portion is covered with the i-type photoelectric conversion layer;
A thin film photoelectric conversion device. The groove portion penetrates each layer from the p-type semiconductor layer to the first electrode layer of the photoelectric conversion unit located closest to the second electrode layer, and separates the layers in the predetermined direction;
The thin film photoelectric conversion device according to claim 1. The photoelectric conversion unit located closest to the second electrode layer among the photoelectric conversion units separated by the groove is provided between the p-type semiconductor layer and the i-type photoelectric conversion layer, and is formed by the groove. Comprising a non-conductive layer separated in a predetermined direction;
The thin film photoelectric conversion device according to claim 2. The non-conductive layer is made of a material containing oxygen;
The thin film photoelectric conversion device according to claim 3. A plurality of the photoelectric conversion units are stacked, provided between the stacked photoelectric conversion units, have conductivity, and have light transmittance and light reflectivity with respect to light of a predetermined wavelength, and the groove has the predetermined direction. Comprising an intermediate layer separated in
The thin film photoelectric conversion device according to claim 1, wherein: One or more light-transmitting first electrode layers, a p-type semiconductor layer, an i-type photoelectric conversion layer, and an n-type semiconductor layer are provided in this order on the light-transmitting insulating substrate. A plurality of photoelectric conversion cells in which a photoelectric conversion unit and a second electrode layer are stacked in this order are arranged in parallel in a predetermined direction, and the adjacent thin-film solar cells are electrically connected in series. A method of manufacturing a thin film photoelectric conversion device,
A first step of forming the first electrode layer on the translucent insulating substrate;
A second step of forming the p-type semiconductor layer on the first electrode layer directly or via one or more photoelectric conversion units;
A plurality of the transparent electrode layers and the first electrodes separated in the predetermined direction by forming a first groove portion reaching the translucent insulating substrate from the uppermost p-type semiconductor layer formed in the second step A third step of forming a layer;
A fourth step of forming the i-type photoelectric conversion layer in the first groove and on the uppermost p-type semiconductor layer so as to cover at least a side wall of the first groove;
A fifth step of forming the n-type semiconductor layer on the i-type photoelectric conversion layer;
A sixth step of forming a second groove portion reaching the first electrode layer from the n-type semiconductor layer formed in the fourth step at a position different from the first groove portion;
The second electrode layer separated for each of the photoelectric conversion cells at the position opposite to the first groove portion of the second groove portion so as to be electrically connected to the first electrode layer in the second groove portion. A seventh step of forming in the second groove and on the n-type semiconductor layer;
Including
A method of manufacturing a thin film photoelectric conversion device characterized by the above. In the second step, a non-conductive layer is formed on the uppermost p-type semiconductor layer,
In the third step, forming a groove reaching the light-transmissive insulating substrate from the nonconductive layer as the first groove,
A method for producing a thin film photoelectric conversion device according to claim 6. The non-conductive layer is made of a material containing oxygen;
The manufacturing method of the thin film photoelectric conversion apparatus of Claim 7 characterized by these. In the second step, an intermediate layer having electrical conductivity and light transmittance and light reflectivity with respect to light of a predetermined wavelength is formed between the photoelectric conversion units laminated,
In the third step, the intermediate layer is separated in the predetermined direction by the first groove portion;
The method for producing a thin-film photoelectric conversion device according to claim 6, wherein:

Images