KR101063694B1 - Solar cell and manufacturing method thereof - Google Patents

Abstract

A solar cell and a method of manufacturing the same are disclosed. A solar cell according to an embodiment includes a plurality of back electrodes spaced apart from each other on a substrate; Light absorption patterns formed on the rear electrodes, respectively; A light transmitting part formed between the light absorption patterns; A contact pattern positioned on one side of the light transmitting part and selectively exposing a part of the back electrode; A front electrode layer formed on the light absorption pattern, the light transmitting part, and the contact pattern; And a separation pattern formed inside the contact pattern to expose a portion of the back electrode and penetrating the front electrode layer. Since the solar cell has a transparent insulating material disposed between the solar cells, light efficiency and light transmittance may be improved.

Solar cell, BIPV

Description

SOLAR CELL AND METHOD OF FABRICATING THE SAME

An embodiment relates to a solar cell and a manufacturing method thereof.

Photovoltaic devices that convert light energy into electrical energy using photoelectric conversion effects are widely used as a means of obtaining pollution-free energy that contributes to the preservation of the global environment.

As photovoltaic change efficiency of solar cells is improved, many solar power systems with photovoltaic devices have been installed outside of commercial buildings as well as in residential applications.

In other words, building integrated photovoltaic (BIPV) technology that uses a solar cell (PV: Photovoltaic) as an outer covering of a building has attracted attention.

This building integration technology satisfies the required performance as a jacket finish and at the same time requires the power supply of the building through its own power generation.

Accordingly, the light transmittance and the light efficiency of the solar cell are important.

The embodiment provides a solar cell and a method for manufacturing the same, which can improve light efficiency while selectively transmitting light by an improved appearance.

A solar cell according to an embodiment includes a plurality of back electrodes spaced apart from each other on a substrate; Light absorption patterns formed on the rear electrodes, respectively; A light transmitting part formed between the light absorption patterns; A contact pattern positioned on one side of the light transmitting part and selectively exposing a part of the back electrode; A front electrode layer formed on the light absorption pattern, the light transmitting part, and the contact pattern; And a separation pattern formed inside the contact pattern to expose a portion of the back electrode and penetrating the front electrode layer.

In accordance with another aspect of the present invention, a method of manufacturing a solar cell includes stacking a back electrode layer and a light absorbing layer on a substrate; Forming a through hole for selectively exposing an upper surface of the substrate, and forming a rear electrode and a light absorption pattern separated from each other by the through hole; Filling a transparent insulating material in the through hole to form a light transmitting part; Forming a contact pattern positioned on one side of the light transmitting part and selectively exposing a part of the back electrode; Forming a front electrode layer on the light absorption pattern, the light transmitting part, and the contact pattern; And forming a separation pattern penetrating the front electrode layer inside the contact pattern to expose a portion of the back electrode.

In the solar cell and the method of manufacturing the same according to the embodiment, a light transmitting part formed of a transparent insulating material is disposed between the solar cells to satisfy power generation efficiency and light transmission at the same time.

That is, since a light transmitting unit is disposed between neighboring solar cells in the BIPV, light may be transmitted through the light transmitting unit.

Since the rear electrode of the solar cell is formed of a metal conductor, it is possible to improve the electrical properties by reducing the series resistance.

The light transmitting part may improve leakage efficiency by preventing leakage current between the solar cells. Since the light transmitting part is formed of a transparent insulating material, neighboring solar cells may be completely separated from each other.

Light may pass through the light-transmitting part to be conducted to the light absorption layer of the solar cell, thereby improving light efficiency.

The light transmitting part may be formed in various colors to form a color light transmitting solar cell.

By controlling the transmission of light by adjusting the position, size and shape of the light transmitting portion, it is possible to improve the light transmittance and aesthetic function. In particular, when the solar cell is used as a building finish of the building, it is possible to further improve the aesthetic function by the light transmitting portion.

In the description of the embodiments, where each substrate, layer, film, or electrode is described as being formed "on" or "under" of each substrate, layer, film, or electrode, etc. , "On" and "under" include both "directly" or "indirectly" formed through other components. In addition, the upper or lower reference of each component is described with reference to the drawings. The size of each component in the drawings may be exaggerated for the sake of explanation and does not mean the size actually applied.

1 to 8 are cross-sectional views illustrating a method of manufacturing the solar cell according to the first embodiment.

Referring to FIG. 1, a back electrode layer 111 is formed on a substrate 100.

The substrate 100 may be glass, and a ceramic substrate, a metal substrate, or a polymer substrate may also be used.

For example, soda lime glass or high strained point soda glass may be used as the glass substrate. As the metal substrate, a substrate including stainless steel or titanium may be used. As the polymer substrate, polyimide may be used.

The substrate 100 may be transparent. The substrate 100 may be rigid or flexible.

The back electrode layer 111 may be formed of a conductor such as metal.

Since the back electrode layer 111 is formed of a metal, the series resistance characteristics may be improved, thereby increasing conductivity. For example, the back electrode layer may have a thickness of about 500 to 1500 nm and a sheet resistance of 1 Ω or less.

For example, the back electrode layer 111 may be formed by a sputtering process using a molybdenum (Mo) target.

This is because of the high conductivity of molybdenum (Mo), ohmic bonding with the light absorbing layer, and high temperature stability under Se atmosphere.

The molybdenum (Mo) thin film, which is the back electrode layer 111, should have a low specific resistance as an electrode and have excellent adhesion to a substrate so that peeling does not occur due to a difference in thermal expansion coefficient.

The material forming the back electrode layer 111 is not limited thereto, and may be formed of molybdenum (Mo) doped with sodium (Na) ions.

Although not shown in the drawing, the back electrode layer 111 may be formed of at least one layer. When the back electrode layer 111 is formed of a plurality of layers, the layers constituting the back electrode layer 111 may be formed of different materials.

Referring to FIG. 2, a light absorbing layer 121 is formed on the back electrode layer 111.

The light absorbing layer 121 includes an Ib-IIIb-VIb-based compound.

In more detail, the light absorbing layer 121 may be formed of a copper-indium-gallium-selenide-based (Cu (In, Ga) Se ₂ , CIGS-based) compound or a copper-indium-selenide-based (CuInSe ₂ , CIS-based) compound. It may include.

For example, in order to form the light absorbing layer 121, a CIG-based metal precursor film is formed on the back electrode layer 111 using a copper target, an indium target, and a gallium target.

Thereafter, the metal precursor film reacts with selenium (Se) by a selenization process to form a CIGS-based light absorbing layer 121.

In addition, the light absorbing layer 121 may form copper (Cu), indium (In), gallium (Ga), selenide (Se) by co-evaporation.

For example, the light absorbing layer 121 may be formed to a thickness of 1000 ~ 2000nm.

The light absorbing layer 121 receives external light and converts the light into electrical energy. The light absorbing layer 121 generates photo electromotive force by the photoelectric effect.

Referring to FIG. 3, a through hole 125 penetrating the light absorbing layer 121 and the back electrode layer 111 is formed.

A plurality of unit cells C1 and C2 including the light absorption pattern 120 and the back electrode 110 may be separated by the through hole 125. That is, the light absorption layer 121 and the back electrode layer 111 are patterned for each unit cell C1 and C2 by the through hole 125 to form the light absorption pattern 120 and the back electrode 110. Can be.

For example, the cell C1 is referred to as a first cell and the cell C2 is referred to as a second cell. In addition, an area between the first cell C1 and the second cell C2 is referred to as a light transmitting area T1.

The through hole 125 may be formed through a mechanical scribing process, and the upper surface of the substrate 100 may be exposed.

The first and second cells C1 and C2 may have a structure in which the rear electrode 110 and the light absorption pattern 120 are stacked, and may be formed to be spaced apart from each other by the through holes 125.

The through hole 125 may be formed to have a width smaller than or equal to the unit cell. For example, the width D1 of the first cell C1 and the width D2 of the through hole 125 may be formed to have 1: 0.5 to 1: 1. Specifically, the width of the through hole 125 may have a width of 2 to 6 mm, but is not limited thereto.

The through hole 125 may be formed in a stripe shape. However, the present invention is not limited thereto and may be formed in various forms such as a matrix form.

Referring to FIG. 4A, a light transmitting part 130 is formed in the light transmitting area T1.

The light transmitting part 130 may be formed of a transparent insulating member.

The transparent insulating member may have a heat resistance of 100 to 200 ° C., and may be a strong alkali, light resistance, and insulating material having a light transmittance of 90 to 100%.

For example, the transparent insulation member may be a transparent amorphous resin, poly methyl methacrylate (PMMA), a copolymer of acrylonitrile and styrene, SAN, PC (poly cabornate), transparent ABS (acrylonitrile butadiene styrene), PET (polyethylene terephtalate), and U. It may be formed of any one of Ultra High Molecular Weight (HMW) ployethylene, MC (methyl cellulose), POM (poly oxy methylene), PTEE (polytetrafluoroethylene), PPO (polypropylene oxide) and PUR (polyurethane). Alternatively, the transparent insulating member may be formed of a positive or negative photoresist.

The light transmitting part 130 may be selectively formed in the through hole 125 through a heat adsorption, injection or filling method.

For example, the light transmitting unit 130 may be formed by any one of a dispensing, inkjet, hot press, and photolithography process.

In addition, when the light transmitting part 130 is formed, a color light transmitting part may be formed by adding color to the transparent insulating member.

An active area and an inactive area are defined on the substrate 100 by the light transmitting part 130. That is, the first and second cells C1 and C2 separated from each other by the light transmitting unit 130 may be used as active regions.

Light incident to the first and second cells C1 and C2, which are active regions, is converted into electrical energy, and light incident to the floodlight 130, which is an inactive region, is not converted to electrical energy. In addition, since the light transmitting part 130 is transparent, light may be transmitted.

Referring again to FIG. 4A, the light transmitting part 130 may be formed at the same height as the light absorption pattern 120.

As shown in FIG. 4B, the light transmitting part 130 may be formed to have a height higher than an upper surface of the light absorption pattern 120. The upper surface of the light transmitting portion 40 may be formed to have a curved surface.

Although not shown, the light transmitting part 40 may be formed to have a height lower than that of the light absorption pattern 120.

The light transmission unit 130 may be formed to have the same width as the unit cell. For example, the widths of the first cell C1 and the light transmitting unit 130 may be configured to have a width of 1: 0.5 to 1: 1.

The cell and the light transmitting unit 130 may be formed to have a structure arranged alternately. That is, the light transmitting part T1 is formed between the first cell C1 and the second cell C2 to satisfy the power generation efficiency and light transmittance of the solar cell.

Since the light emitter 130 is formed between the first and second cells C1 and C2, leakage current generated between the first and second cells C1 and C2 may be prevented. .

That is, in the exemplary embodiment, the light transmitting part 130 made of an insulating material is formed between the first and second cells C1 and C2. Therefore, by removing the leakage current between the cells to secure the shunt resistance (Rsh) can improve the open voltage (Voc).

In addition, the light passing obliquely with respect to the light transmitting part 130 may be conducted to the light absorbing layer 30 to improve the light efficiency of the light absorbing layer 30.

Referring to FIG. 5, a buffer layer 141 and a high resistance buffer layer 151 are formed on the cells C1 and C2 and the light transmitting part 130.

The buffer layer 141 may be formed of at least one layer on the light absorption pattern 120 and the light transmitting part 130, and may be formed by stacking cadmium sulfide (CdS).

In this case, the buffer layer 141 is an n-type semiconductor layer, and the light absorption pattern 40 is a p-type semiconductor layer. Therefore, the light absorption pattern 120 and the buffer layer 141 form a pn junction.

A zinc oxide layer may be further formed on the cadmium sulfide (CdS) by performing a sputtering process targeting the zinc oxide (ZnO).

The buffer layer 41 has a refractive index of about 2.2 to 2.6.

The high resistance buffer layer 151 may be formed as a transparent electrode layer on the buffer layer 141.

For example, the high resistance buffer layer 151 may be formed of any one of ITO, ZnO, and i-ZnO.

The high resistance buffer layer 151 has a refractive index of about 1.7 to 2.1.

The buffer layer 141 and the high resistance buffer layer 151 are disposed between the light absorption pattern 120 and the front electrode to be formed later.

That is, since the light absorption pattern 120 and the front electrode have a large difference between the lattice constant and the energy band gap, the buffer layer 141 and the high resistance buffer layer 151 having a band gap in between the two materials are inserted into the light absorbing pattern 120 and the front electrode. Good bonding can be formed.

In the exemplary embodiment, two buffer layers are formed on the light absorption pattern 120, but the present invention is not limited thereto. The buffer layer may be formed of only one layer.

Referring to FIG. 6, a contact pattern 155 penetrating the light absorption pattern 120, the buffer layer 141, and the high resistance buffer layer 151 is formed.

The contact pattern 155 may be formed by a mechanical process or a laser process, and a portion of the back electrode 110 is exposed.

For example, the contact pattern 155 may selectively expose the back electrode 110 corresponding to the second cell C2 located on one side of the light transmitting part 130.

The contact pattern 155 may have a width of about 90 μm to about 150 μm.

The buffer layer 140 and the high resistance buffer layer 150 may be separated by unit cells by the contact pattern 155.

Referring to FIG. 7, a transparent conductive material is stacked on the high resistance buffer layer 150 to form a front electrode layer 161 and a connection wiring 171.

When the front electrode layer 161 is stacked on the high resistance buffer layer 150, a transparent conductive material may also be inserted into the contact pattern 155 to form the connection wiring 171.

Therefore, the back electrode 110 and the front electrode layer 161 may be electrically connected by the connection wiring 171.

The front electrode layer 161 may be formed of zinc oxide or indium tin oxide (ITO) including impurities such as aluminum (Al), alumina (Al ₂ O ₃ ), magnesium (Mg), and gallium (Ga). .

For example, the front electrode layer 161 may be formed of zinc oxide doped with aluminum or alumina by a sputtering process to form an electrode having a low resistance value.

That is, the front electrode layer 161 is a window layer forming a pn junction with the light absorption pattern 120. Since the front electrode layer 161 functions as a transparent electrode on the front of the solar cell, zinc oxide having high light transmittance and high electrical conductivity ( ZnO).

For example, the front electrode layer 161 may be formed to a thickness of about 200 ~ 800nm. In addition, the front electrode layer 161 has a sheet resistance of about 10 to 30 Ω, and may have a light transmittance of about 80 to 90%.

Referring to FIG. 8, a separation pattern 165 penetrating the front electrode layer 161 and the connection wiring 171 is formed.

The separation pattern 165 may be formed by irradiating a mechanical process or a laser. The back electrode 110 exposed by the contact pattern 155 may be selectively exposed.

That is, the separation pattern 165 may expose a portion of the back electrode 110 of the second cell C2. For example, the width of the separation pattern 75 may be formed to 30 ~ 90㎛.

The separation pattern 75 is formed to have a width of a pattern capable of separating the first cell C1 and the second cell C2 so that the first cell C1 and the second cell C2 can be distinguished from each other. have.

That is, each front electrode 170 may be formed on the first cell C1 and the second cell C2 by the separation pattern 75.

The separation pattern 75 may be formed in a stripe form or a matrix form, and may be formed in various forms without being limited to the above form.

The separation pattern 75 is formed such that a part of the connection wiring 170 connected to the front electrode 160 of the first cell C1 remains. This is because the separation pattern 165 is formed such that a part of the connection wiring 170 formed on the side surface of the light transmitting part 130 remains.

Therefore, each cell may be connected to each other by the connection wiring 170. That is, the connection wiring 170 electrically connects the back electrode 110 of the second cell C2 and the front electrode 160 of the first cell C1 adjacent to the second cell C2. do.

9 is a plan view schematically illustrating the solar cell illustrated in FIG. 8.

Referring to FIGS. 8 and 9, a solar cell may have a light transmissive region formed between solar cells. That is, the light transmitting part 130 is formed in the light transmitting area T1 between the first cell C1 and the second cell C2, and the solar cells C1, C2... Cn and the light transmitting area T1. , T2 ... Tn-1) may be formed alternately.

In addition, the width of the light transmission area T1 may be formed to be the same width as the solar cell (C1). However, the present invention is not limited thereto, and the light transmission may be controlled by adjusting the position, size, and shape of the light transmitting region T1.

As described above, the light transmitting region T1 is formed between the solar cells, thereby improving power generation efficiency and light transmittance of the solar cell.

In addition, generation of a leakage current between the solar cells may be prevented by the light transmitting area T1.

The solar cell includes a back electrode 110, a light absorption pattern 120, a buffer layer 140, a high resistance buffer layer 150, and a front electrode layer 160.

The back electrode 110 is formed of a metal, and the width thereof can be adjusted to be as small as possible, thereby improving light efficiency. Accordingly. It is possible to improve the light efficiency by improving the series resistance characteristics of the solar cell.

The buffer layer 140, the high resistance buffer layer 150, and the front electrode layer 160 may be disposed on the light transmitting part 130 formed between the solar cells.

That is, the light passing through the light transmission area T1 may proceed to the light absorption pattern 120 according to the refractive indices of the layers formed on the light transmission area T1.

For example, the refractive index of ZnO is 1.9, the refractive index of CdS is 2.4, and the refractive index of CIGS is 2.9.

Therefore, since the light transmission region T1 may have a refractive index of 2.4 to 2.9, light may be refracted by the light absorption pattern 120.

10 to 16 are cross-sectional views illustrating a method of manufacturing the solar cell according to the second embodiment. In the second embodiment, detailed descriptions of the components and the components operating in the same manner as in the first embodiment will be omitted.

Referring to FIG. 10, a back electrode layer 211 is formed on a substrate 200.

The substrate 200 may be glass, and a ceramic substrate such as alumina, a stainless steel, a titanium substrate, or a polymer substrate may also be used.

The back electrode layer 211 may be formed of a conductor such as metal.

For example, the back electrode layer 211 may be formed by a sputtering process using a molybdenum (Mo) target.

Referring to FIG. 11, a light absorbing layer 221, a buffer layer 241, and a high resistance buffer layer 251 are formed on the back electrode layer 211.

The light absorbing layer 221 may include a copper-indium-gallium-selenide-based (Cu (In, Ga) Se ₂ , CIGS-based) compound or a copper-indium-selenide-based (CuInSe ₂ , CIS-based) compound. have.

For example, the buffer layer 241 is formed by laminating cadmium sulfide (CdS) on the light absorbing layer 221, and the high resistance buffer layer 251 is formed by laminating zinc oxide on the buffer layer 241. Can be.

Since the process of forming the light absorbing layer 221, the buffer layer 241 and the high resistance buffer layer 251 is the same as that of FIGS. 2 and 5 of the first embodiment, description thereof will be omitted.

12, a through hole 255 penetrating the high resistance buffer layer 251, the buffer layer 241, the light absorbing layer 221, and the back electrode layer 211 is formed.

The through hole 255 may selectively expose the substrate 200.

The high resistance buffer layer 251, the buffer layer 241, the light absorbing layer 221, and the back electrode layer 211 may be patterned for each unit cell C1 and C2 by the through hole 255. For example, the cell C1 is referred to as a first cell and the cell C2 is referred to as a second cell. The light transmitting area T1 may be between the first cell C1 and the second cell C2.

The through hole 255 may be formed by irradiating a mechanical process or a laser, and may be formed to expose the top surface of the substrate 200.

The first and second cells C1 and C2 have a structure in which a rear electrode 210, a light absorption pattern 220, a buffer pattern 240, and a high resistance buffer pattern 250 are stacked. The neighboring cells may be formed to be spaced apart from each other by the hole 255.

The through hole 255 may be formed to have the same width as that of the unit cell. For example, the width of the first cell C1 and the width of the through hole may be formed to have 1: 0.5 to 1: 1.

The through hole 255 may be formed in a stripe shape. However, the present invention is not limited thereto and may be formed in various forms such as a matrix form.

Referring to FIG. 13, a light transmitting part 230 is formed in the through hole 255.

The light transmitting part 230 may be formed of a transparent insulating member such as a transparent amorphous resin or a photoresist.

The light transmitting part 230 may be selectively formed in the through hole 255 through a heat adsorption, injection or filling method.

The light transmitting part 230 may be formed at the same height as the high resistance buffer pattern 250 positioned at the top of the unit cell. Alternatively, the light transmitting part 230 may have a height higher or lower than that of the high resistance buffer pattern 250.

Since the process of forming the light transmitting portion 230 is the same as in Figures 4a and 4b of the first embodiment, description thereof will be omitted.

Referring to FIG. 14, a contact pattern 256 penetrating the high resistance buffer pattern 250, the buffer pattern 240, and the light absorption pattern 220 is formed.

For example, the contact pattern 256 may selectively expose the back electrode 210 corresponding to the second cell C2 positioned on one side of the light transmitting part 230.

Referring to FIG. 15, a transparent conductive material is stacked on the high resistance buffer pattern 250 and the light transmitting part 230 to form a front electrode layer 261 and a connection wiring 271.

When the front electrode layer 261 is stacked on the high resistance buffer pattern 250, a transparent conductive material may be inserted into the contact pattern 256 to form the connection wiring 271.

Accordingly, the back electrode 210 and the front electrode layer 261 exposed by the contact pattern 265 may be electrically connected by the connection wiring 271.

The front electrode layer 261 may be formed of zinc oxide or indium tin oxide (ITO) including impurities such as aluminum (Al), alumina (Al ₂ O ₃ ), magnesium (Mg), and gallium (Ga). .

Referring to FIG. 16, a separation pattern 265 is formed through the front electrode layer 261 and the connection wiring 271.

The separation pattern 265 may be formed by irradiating a mechanical process or a laser and forming a portion of the back electrode 210 exposed by the contact pattern 256. can do.

The separation pattern 265 is formed to have a width of a pattern capable of separating the first cell C1 and the second cell C2 so that the first cell C1 and the second cell C2 can be distinguished from each other. have. That is, each front electrode layer 260 may be formed on the first cell C1 and the second cell C2 by the separation pattern 265.

The separation pattern 265 is formed such that a part of the connection wiring 270 connected to the front electrode layer 260 of the first cell C1 remains. This is because the separation pattern 265 is formed such that a part of the connection wiring 270 formed on the side surface of the light transmitting part 230 remains.

Therefore, each cell may be connected to each other by the connection wiring 270. That is, the connection wiring 270 electrically connects the back electrode 210 of the second cell C2 and the front electrode layer 260 of the first cell C1 adjacent to the second cell C2. do.

17 to 24 are cross-sectional views illustrating a structure of a solar cell according to a third embodiment. In the third embodiment, detailed descriptions of components and components operated in the same manner as in the first and second embodiments will be omitted.

Referring to FIG. 17, a back electrode layer 311, a light absorbing layer 321, and a buffer layer 341 are formed on the substrate 300.

Referring to FIG. 18, a through hole 345 penetrating the buffer layer 341, the light absorbing layer 321, and the back electrode layer 311 is formed.

The buffer layer 341, the light absorbing layer 321, and the back electrode layer 311 may be patterned for each unit cell C1 and C2 by the through hole 345.

For example, the cell C1 is referred to as a first cell and the cell C2 is referred to as a second cell. In addition, the light emitting area T1 may be formed between the first cell C1 and the second cell C2.

The through hole 345 may be formed by irradiating a mechanical process or a laser, and may be formed to expose the top surface of the substrate 300.

The first and second cells C1 and C2 have a structure in which a rear electrode 310, a light absorption pattern 320, and a buffer pattern 340 are stacked and neighboring cells by the through hole 345. May be formed to be spaced apart from each other.

The through hole 345 may be formed to have the same width as the unit cell. For example, the width of the first cell C1 and the width of the through hole 345 may be 1: 0.5 to 1: 1.

Referring to FIG. 19, a light transmitting part 330 is formed in the through hole 345.

The light transmitting part 330 may be formed of a transparent insulating member such as a transparent amorphous resin or a photoresist.

The light transmitting portion 330 may be selectively formed in the through hole 345 through a heat adsorption, injection or filling method.

The light transmitting part 330 may be formed at the same height as the buffer pattern 340 positioned at the top of the unit cell. Alternatively, the light transmitting part 330 may have a height higher or lower than that of the buffer pattern 340.

Since the process of forming the light transmitting portion 230 is the same as in Figures 4a and 4b of the first embodiment, description thereof will be omitted.

Referring to FIG. 20, a high resistance buffer layer 351 is formed on the buffer pattern 340 and the light transmitting part 330.

The high resistance buffer layer 351 may be formed as a transparent electrode layer on the buffer pattern 340.

Referring to FIG. 21, a contact pattern 355 penetrating the light absorption pattern 320, the buffer pattern 340, and the high resistance buffer layer 351 is formed.

For example, the contact pattern 355 may selectively expose the back electrode 310 corresponding to the second cell C2 located on one side of the light transmitting part 330.

Referring to FIG. 22, a transparent conductive material is stacked on the high resistance buffer layer 351 and the contact pattern 355 to form a front electrode layer 361 and a connection wiring 371.

When the front electrode layer 361 is stacked on the high resistance buffer layer 351, a transparent conductive material may also be inserted into the contact pattern 355 to form the connection wiring 371.

Therefore, the back electrode 310 and the front electrode layer 361 may be electrically connected by the connection wiring 371.

Referring to FIG. 23, a separation pattern 365 penetrating the front electrode layer 361 and the connection wiring 371 is formed.

The separation pattern 365 may be formed by irradiating a mechanical process or a laser and forming a portion of the back electrode 310 exposed by the contact pattern 355. can do.

The separation pattern 365 is formed to have a width of a pattern capable of separating the first cell C1 and the second cell C2 so that the first cell C1 and the second cell C2 can be distinguished from each other. have. That is, each front electrode layer 260 may be formed on the first cell C1 and the second cell C2 by the separation pattern 365.

The separation pattern 365 is formed such that a part of the connection wiring 370 connected to the front electrode layer 360 of the first cell C1 remains.

Therefore, each cell may be connected to each other by the connection wiring 370. That is, the connection wiring 370 electrically connects the back electrode 310 of the second cell C2 and the front electrode layer 360 of the first cell C1 adjacent to the second cell C2. do.

Although the above description has been made based on the embodiments, these are merely examples and are not intended to limit the present invention. Those skilled in the art to which the present invention pertains may not have been exemplified above without departing from the essential characteristics of the present embodiments. It will be appreciated that many variations and applications are possible. For example, each component specifically shown in the embodiment can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

1 to 8 are cross-sectional views illustrating a method of manufacturing the solar cell according to the first embodiment.

9 is a plan view of the solar cell module shown in FIG. 8.

10 to 16 are cross-sectional views illustrating a method of manufacturing the solar cell according to the second embodiment.

17 to 23 are cross-sectional views illustrating a method of manufacturing a solar cell according to a third embodiment.

Claims (9)

A plurality of back electrodes formed on the substrate and spaced apart from each other by through holes selectively exposing an upper surface of the substrate; Light absorption patterns formed on the rear electrodes, respectively; A light transmitting part formed between the light absorption patterns; A contact pattern positioned on one side of the light transmitting part and selectively exposing a part of the back electrode; A front electrode layer formed on the light absorption pattern, the light transmitting part, and the contact pattern; And And a separation pattern formed inside the contact pattern to expose a portion of the back electrode and penetrating the front electrode layer. The method of claim 1, The light transmitting portion is a solar cell formed of a transparent amorphous resin or photoresist. The method of claim 1, The light transmitting part has a light transmittance of 90 to 100%, a solar cell having a refractive index of 1.9 ~ 2.9. The method of claim 1, And a buffer layer selectively formed on the light absorption pattern by the contact pattern. The method of claim 1, A solar cell comprising a buffer layer formed on the light absorption pattern and the light transmitting portion. The method of claim 1, The light transmitting portion is a solar cell formed at least the same height as the light absorption pattern. The method of claim 1, A width of the light absorption pattern and the light transmitting portion of the solar cell formed 1: 1: 0.5. Stacking a back electrode layer and a light absorbing layer on the substrate; Forming a through hole for selectively exposing an upper surface of the substrate, and forming a rear electrode and a light absorption pattern separated from each other by the through hole; Filling a transparent insulating material in the through hole to form a light transmitting part; Forming a contact pattern positioned on one side of the light transmitting part and selectively exposing a part of the back electrode; Forming a front electrode layer on the light absorption pattern, the light transmitting part, and the contact pattern; And Forming a separation pattern penetrating the front electrode layer inside the contact pattern to expose a portion of the back electrode. The method of claim 8, The light transmitting portion is formed of a transparent amorphous resin and a photoresist, and a method of manufacturing a solar cell formed by a heat adsorption, injection or filling method.

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