KR20120074182A - Solar cell and method of manufacturing the same - Google Patents

Abstract

PURPOSE: A solar cell and a manufacturing method thereof are provided to improve the reliability and efficiency by reducing a gap of a second scribe area. CONSTITUTION: A dummy pattern(200) is formed on one side of a substrate(100). A first conductive layer(300) is formed on the substrate and the dummy pattern. A light absorption layer(400) is formed on the first conductive layer. A buffer layer(500) and a window layer(600) are formed on the light absorption layer.

Description

Solar cell and method of manufacturing the same

TECHNICAL FIELD This invention relates to a solar cell and its manufacturing method. Specifically, It is related with the solar cell using a compound semiconductor, and its manufacturing method.

Solar cells are key components of solar power generation that convert sunlight directly into electricity. Solar cells are used as power sources for portable electronic devices such as clocks and calculators, or in various forms, ranging from small-scale distributed generation on the roof of a building to industrial power generation on a large open ground.

Solar cells can generally be classified into monocrystalline silicon solar cells, polycrystalline silicon solar cells and thin film solar cells. Among them, although the conversion efficiency is lower than that of monocrystalline and polycrystalline silicon solar cells, thin-film solar cells that can reduce the thickness of the substrate and can be manufactured on inexpensive substrates such as glass and can be reduced in price have attracted attention.

The thin film solar cell has a structure in which a light absorbing layer, a buffer layer, and a window layer are provided between a first conductive layer and a second conductive layer spaced apart from each other on a substrate. In addition, research on thin film solar cells using CdTe and CuInGaSe ₂ compound semiconductors having relatively high conversion efficiency as a material for the light conversion layer is increasing. In particular, various attempts have been made to further increase the conversion efficiency of a thin film solar cell using a CuInGeSe ₂ compound semiconductor having excellent conversion efficiency.

On the other hand, a plurality of mechanical scribing processes are performed to produce thin film solar cells. That is, after the first conductive layer is formed, the first scribing process is performed, after the light absorbing layer and the buffer layer are formed, the second scribing process is performed, and after the second conductive layer is formed, the third scribe is performed. Perform the ice process. Here, the second scribing region is embedded with a second conductive layer formed thereafter, and the second conductive layer and the first conductive layer are electrically connected to each other. A method of manufacturing such a thin film solar cell is disclosed in, for example, Korean Patent Registration No. 10-1034146 and Korean Patent Publication No. 2011-0035797. Korean Patent No. 10-1034146 discloses a solar cell for forming an alloy layer selectively containing Ag elements on a first conductive layer, and Korean Patent Publication No. 2011-0035797 discloses a Group I, A solar cell is disclosed that forms an alloy layer comprising any one of Group III-Group I-Group III compounds. However, these prior patents carry out a process of filling the second conductive layer after forming the second scribing region.

However, a large step is generated between the upper part and the lower part by the second scribing region, and the second scribing region needs to be buried, so that the second conductive layer may be disconnected unless the second conductive layer is thickly formed. It may be. Accordingly, there is a problem that the efficiency and reliability is lowered.

The present invention provides a solar cell and a method of manufacturing the same that can improve efficiency and reliability.

The present invention provides a solar cell and a method of manufacturing the same, which can alleviate the unevenness of the surface caused by the step difference of the second scribing region and reduce the step difference of the second conductive layer formed thereafter, thereby preventing the disconnection of the second conductive layer. .

The present invention provides a solar cell and a method of manufacturing the same, by forming a dummy pattern in the second scribing region and then forming thin films to improve the efficiency and reliability by reducing the step difference in the second scribing region.

The present invention provides a solar cell and a method of manufacturing the same that can increase efficiency by increasing the light conversion region.

A solar cell according to an aspect of the present invention includes a dummy pattern formed in one region on a substrate; A first conductive layer formed on the substrate and the dummy pattern; A light absorbing layer formed on the first conductive layer on the substrate; And a second conductive layer formed on the light absorbing layer and the first conductive layer on the dummy pattern.

According to another aspect of the present invention, a solar cell includes a dummy pattern formed in one region on a substrate; A first conductive layer formed on the substrate along a side surface from an upper portion of the dummy pattern; A light absorbing layer formed on the first conductive layer on the substrate; And a second conductive layer formed on the first conductive layer on the light absorbing layer and the dummy pattern, wherein the second conductive layer is formed on the dummy pattern side surface and the first conductive layer on the substrate through the first conductive layer on the dummy pattern. Connected with layers.

A first scribing region provided by removing a predetermined region of the first conductive layer on the substrate; A second scribing region spaced apart from the first scribing region by a predetermined distance; And a third scribing region in which predetermined regions of the second conductive layer and the light absorbing layer are removed to be spaced apart from the second scribing region by a predetermined interval.

The dummy pattern is formed on the second scribing region or is formed to at least partially overlap the third scribing region, and the dummy pattern is formed of an insulating material.

At least one side surface of the dummy pattern is formed to be inclined.

The dummy pattern is formed to have a flat upper surface in consideration of the thicknesses of the first conductive layer and the light absorbing layer.

Further comprising a buffer layer and a window layer formed on the light absorbing layer.

According to another aspect of the present invention, there is provided a method of manufacturing a solar cell, the method including: forming a dummy pattern in one region on a substrate; Forming a first conductive layer on the substrate and the dummy pattern; Removing the light absorbing layer remaining on the dummy pattern after forming the light absorbing layer on the first conductive layer; And forming a second conductive layer on the first conductive layer on the light absorbing layer and the dummy pattern.

Removing a predetermined region of the first conductive layer on the substrate from one side of the dummy pattern to form a first scribing region; And forming a third scribing region by removing predetermined regions of the second conductive layer and the light absorbing layer so as to be spaced apart from the other side of the dummy pattern by a predetermined interval.

Removing a predetermined region of the first conductive layer on the substrate from one side of the dummy pattern to form a first scribing region; And removing a predetermined region of the second conductive layer and the light absorbing layer to at least partially overlap the dummy pattern to form a third scribing region.

The dummy pattern is formed using an insulating material.

At least one side surface of the dummy pattern is formed to be inclined.

In the solar cell according to the embodiment of the present invention, a dummy pattern is formed in the second scribing region, a first conductive layer is formed on the substrate along the side surface from an upper surface of the dummy pattern, and a light absorbing layer is formed in the region except the dummy pattern. After the buffer layer and the window layer are formed to planarize the top surface, a second conductive layer is formed.

Therefore, since the second conductive layer is formed on the flat surface where the step is not generated, there is no problem of disconnection of the second conductive layer, thereby improving efficiency and reliability of the solar cell. In addition, the first conductive layer and the second conductive layer of adjacent cells are physically and electrically connected to each other by the first conductive layer formed on the dummy pattern, thereby enabling normal operation of the solar cell.

1 is a cross-sectional view of a solar cell according to an embodiment of the present invention.
2 is a cross-sectional view of a solar cell according to another embodiment of the present invention.
3 to 8 are cross-sectional views sequentially illustrating a method of manufacturing a solar cell according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention; However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention and to those skilled in the art. It is provided for complete information.

1 is a cross-sectional view of a solar cell according to an embodiment of the present invention.

Referring to FIG. 1, a solar cell according to an exemplary embodiment of the present invention includes a dummy pattern 200 formed in a predetermined region on a substrate 100 and a first conductive layer formed on the substrate 100 and the dummy pattern 200. 300, the light absorbing layer 400 formed on the first conductive layer 300, the buffer layer 500 and the window layer 600 formed on the light absorbing layer 400, the window layer 600, and the dummy. The second conductive layer 700 formed on the pattern 200 is included. In addition, the predetermined region of the first conductive layer 300 is removed to provide the first scribing region S1, and the dummy pattern 200 is provided in the second scribing region S, and the second conductive layer is provided. Predetermined regions of the layer 700, the window layer 600, the buffer layer 500, and the light absorbing layer 400 are removed to form a third scribing region S3.

The substrate 100 may use a substrate having various characteristics depending on the use. For example, a transparent substrate, an opaque or semitransparent substrate may be used depending on the light transmitting characteristics. In addition, the substrate 100 may use a glass substrate, a ceramic substrate, a metal substrate, a polymer substrate, or the like depending on the material. The substrate 100 may use a rigid substrate or a flexible substrate according to bending characteristics. Such a substrate 100 may preferably use a glass substrate having light transmittance and low cost. As the glass substrate, for example, soda lime glass (sodalime galss) or high strained soda glass (high strained point soda glass) can be used. In addition, a substrate including stainless steel or titanium may be used as the metal substrate, and polyimide may be used as the polymer substrate.

The dummy pattern 200 is formed in a predetermined region on the substrate 100, preferably in a second scribing region S2. That is, in the related art, after forming the light absorbing layer 400, the buffer layer 500, and the window layer 600, the predetermined scribe regions are scribed to form the second scribing region S2. The dummy pattern 200 is formed in the scribing region S2. The dummy pattern 200 is formed to have a width equal to at least the width of the second scribing region S2. In addition, the dummy pattern 200 may be formed such that at least one side thereof is inclined. That is, the dummy pattern 200 is provided between the first scribing region S1 and the third scribing region S3, and at least the dummy pattern 200 adjacent to the third scribing region S3. One side of may be formed to be inclined. Since one side of the dummy pattern 200 is inclined, the first conductive layer 300 and the light absorbing layer 400 may be easily formed on one side of the dummy pattern 200. That is, when one side of the dummy pattern 200 is formed in a vertical shape, the first conductive layer 300 may not be formed on one side of the dummy pattern 200, and accordingly, the first conductive layer may be formed on the top surface of the dummy pattern 200. The solar cell may be in an inoperable state because the layer 300 and the first conductive layer 300 on the substrate 100 are not connected. Therefore, the dummy pattern 200 may be formed such that one side thereof is inclined so that the lower portion thereof is wider than the upper portion thereof. At this time, the width of the upper portion of the dummy pattern 200 is formed to be the same or narrower than the width of the second scribing region (S2), the width of the lower portion is wider or the same as the width of the second scribing region (S2). Can be formed. Preferably, the dummy pattern 200 may be formed to have a width at an upper portion smaller than a width of the second scribing region S2 and a width at a lower portion equal to a width of the second scribing region S2. In addition, the dummy pattern 200 is formed in consideration of the thicknesses of the first conductive layer 300, the light absorbing layer 400, the buffer layer 500, and the window layer 600, from the dummy pattern 200. The dummy pattern 200 is predetermined so that the thickness of the first conductive layer 300 thereon is preferably equal to the thickness of the light absorbing layer 400, the buffer layer 500, and the window layer 600 outside the dummy pattern 200. Form to thickness. By forming the dummy pattern 200, the entire upper surface including the second scribing region S2 may be formed flat, thereby preventing disconnection of the second conductive layer 700. Meanwhile, the dummy pattern 200 may be formed using an insulating material. Various materials may be used as the insulating material. For example, a silicon-based insulating material such as a silicon oxide film or a silicon nitride film may be used, and a material such as an insulating polymer may be used. In addition, the insulating material may be formed to form the dummy pattern 200, and then may be patterned using a photo mask and an etching process using a predetermined mask, and the insulating material is formed in a state in which a predetermined shadow mask is formed in the shape of the dummy pattern 200. The dummy pattern 200 may also be formed by forming a. On the other hand, the dummy pattern 200 may be formed using the same material as the substrate 100 when using the substrate 100 of the insulating material. For example, in the case of using the glass substrate 100, a dummy pattern 200 may be formed by attaching a stripe-shaped glass pattern on the glass substrate 100 or etching a predetermined portion in the region where the dummy pattern 200 is to be formed. After forming the mask, the glass substrate 100 may be etched to use an unetched region of the glass substrate 100 as the dummy pattern 200.

The first conductive layer 300 is formed on the substrate 100 and the conductive pattern 200, and the first conductive layer 300 formed on the substrate 100 has a predetermined region removed so that the first scribing region ( S1) is formed. That is, the first conductive layer 300 is formed in the entire region except the first scribing region S1, and the substrate (from the upper surface of the dummy pattern 200 to the first scribing region S1 along the side surface) is formed. Formed continuously on 100). Meanwhile, the first scribing region S1 may be formed in the same direction as the terminal pattern 200 formed in the pattern of the second scribing region S2. The first conductive layer 300 may be formed using a conductive material such as metal, and may be formed of a single layer or a plurality of layers of different materials. In this case, it is preferable to use a material having a low specific resistance and excellent adhesion to the substrate 100 so that the first conductive layer 300 does not peel off due to a difference in thermal expansion coefficient. As the first conductive layer 300, chromium (Cr), molybdenum (Mo), an alloy of chromium and molybdenum may be used. In particular, it is preferable to use molybdenum (Mo) having high electrical conductivity, excellent ohmic characteristics with the light absorbing layer 400, and excellent high temperature stability in a selenium (Se) atmosphere as the first conductive layer 300. Do. In addition, the first conductive layer 300 may be formed by doping sodium (Na) ions to the conductive material.

The light absorbing layer 400 absorbs sunlight incident from the outside to generate an electromotive force. The light absorbing layer 400 is formed in a predetermined region on the first conductive layer 300 formed on the substrate 100. That is, the light absorbing layer 400 is not formed on the dummy pattern 200 and is not formed in the third scribing region S3. The light absorbing layer 400 may be formed of, for example, an I-III-VI compound. That is, the light absorbing layer 400 is formed of a copper-indium-gallium-selenide (Cu (In, Ga) Se ₂ , CIGS) compound, or a copper-indium-selenide (CuInSe ₂ , CIS) compound or copper-gallium It can be formed of a selenide (CuGaSe ₂ , CGS) compound. The light absorbing layer 400 may be formed in various ways. For example, the first conductive layer 300 may be sputtered by using a copper target, an indium target, and a gallium target, or by using a mixed target of copper, indium, and gallium. And forming a CIG metal precursor film on the first scribe region S1 and the dummy pattern 200 and then performing selenization process using selenium (Se) at a high temperature to thereby absorb the light absorbing layer of the CIGS compound. 400 may be formed. In addition, the light absorbing layer 400 may form copper, indium, gallium, selenium (Cu, In, Ga, Se) by co-evaporation.

The buffer layer 500 may be formed of at least one layer on the light absorbing layer 400. The buffer layer 500 may be formed of cadmium sulfide (CdS), for example, by chemical bath deposition (CBD). The window layer 600 may be formed of a transparent conductive material on the buffer layer 500. For example, the window layer 600 may be formed of any one of ITO, ZnO, and i-ZnO. The window layer 600 may be formed in various ways. For example, the window layer 600 may be formed of a ZnO layer by a sputtering process targeting ZnO, or a ZnO layer may be formed using a Zn target in an oxygen atmosphere. The buffer layer 500 and the window layer 600 are formed between the light absorbing layer 400 and the second conductive layer 700 formed thereon so that the light absorbing layer 400 and the second conductive layer 700 are well bonded. do. That is, since the light absorption layer 400 and the second conductive layer 700 have a large difference between the lattice constant and the energy band gap, the light absorption layer is formed by forming the buffer layer 500 and the window layer 600 having the intermediate band gap of the two materials. The 400 and the second conductive layer 700 may be bonded well.

The second conductive layer 700 may be formed using a conductive material such as metal, for example, aluminum. In addition, the second conductive layer 700 may be formed of a transparent conductive material so that the second conductive layer 700 may function as a transparent electrode on the front surface of the solar cell. For example, the second conductive layer 700 may be formed using a transparent conductive oxide having a high light transmittance such as ZnO. . In addition, the second conductive layer 700 having a low resistance value may be formed by doping ZnO with aluminum or alumina. On the other hand, the second conductive layer 700 may be formed by various methods, for example, by using a ZnO target by RF sputtering method, a reactive sputtering method using a Zn target, and an organometallic chemical vapor deposition method and the like. Can be formed. In addition, an indium tin oxide (ITO) thin film having excellent electro-optic properties may be deposited on the ZnO thin film to form a second conductive layer 700 having a dual structure.

As described above, in the solar cell according to the exemplary embodiment of the present invention, a dummy pattern 200 is formed in the second scribing region S2, and is formed on the substrate 100 along a side surface from an upper surface of the dummy pattern 200. As a result, the first conductive layer 300 is formed. In addition, the light absorbing layer 400, the buffer layer 500, and the window layer 600 are formed in the region except for the dummy pattern 200 so that the upper surface is planarized, and then the second conductive layer 700 is formed. Therefore, since the second conductive layer 700 is formed on a flat surface where no step is generated, the problem of disconnection of the second conductive layer 700 does not occur, thereby improving efficiency and reliability of the solar cell. In addition, the first conductive layer 300 and the second conductive layer 700 of adjacent cells may be physically and electrically connected to each other by the first conductive layer 300 formed on the dummy pattern 200.

Meanwhile, as shown in FIG. 2, the third scribing region S3 may be formed to partially overlap the dummy pattern 200. In this case, the second conductive layer 700 of the adjacent cell is separated by the third scribing region S3. In this case, the dead zone by the third scribing region S3 may be reduced, thereby improving efficiency of the solar cell. In this case, the dummy pattern 200 may be formed to have a wider width in consideration of the width of the third scribing region S3.

3 to 8 are cross-sectional views sequentially illustrating a method of manufacturing a solar cell according to an embodiment of the present invention.

Referring to FIG. 3, a dummy pattern 200 is formed in a predetermined region on the substrate 100.

The substrate 100 may use a substrate having various characteristics according to the use, and preferably, a glass substrate having light transmittance. In addition, the dummy pattern 200 is formed in a predetermined region on the substrate 100, and preferably in the second scribing region S2. The dummy pattern 200 may be formed to extend in one direction spaced apart from the substrate 100 by a predetermined interval, and thus the dummy pattern 200 may be formed in various shapes such as, for example, a stripe shape or a matrix shape. have. In addition, the dummy pattern 200 may be formed, for example, in a width of 50 μm to 100 μm, and at least one side surface is formed to be inclined so that an upper width thereof is smaller than a lower width thereof. The dummy pattern 200 may be formed of an insulating material. In addition, when the insulating substrate 100 is used, the dummy pattern 200 may be formed of the same material as the substrate 100. In this case, the dummy pattern 200 may be formed by, for example, attaching a glass pattern onto the substrate 100. On the other hand, in order to form at least one side of the dummy pattern 200 to be inclined may be processed using a laser or a needle (needle). As such, at least one side surface of the dummy pattern 200 is inclined so that the first conductive layer 300 formed later may be formed on the substrate 100 along the side surface from the top surface of the dummy pattern 200.

Referring to FIG. 4, after the first conductive layer 300 is formed over the entire surface including the substrate 100 and the dummy pattern 200, a predetermined region of the first conductive layer 300 on the substrate 100 is removed. The first scribing region S1 is formed.

The first conductive layer 300 may use chromium (Cr), molybdenum (Mo), an alloy of chromium and molybdenum, and particularly have high electrical conductivity, excellent ohmic characteristics with the light absorbing layer, and selenium (Se). It is preferable to use molybdenum (Mo) which is excellent in high temperature stability in an atmosphere. The first conductive layer 300 may be formed in various ways. For example, the first conductive layer 300 may be formed by a sputtering process using a metal target. Meanwhile, sodium (Na) ions may be doped into the conductive material of the first conductive layer 300.

In addition, the first scribing region S1 is formed by exposing the predetermined region of the substrate 100 by removing the predetermined region of the first conductive layer 300. The first conductive layer 300 may be arranged in a stripe form or a matrix form by the first scribing region S1, and may correspond to each cell. Of course, the first conductive layer 300 is not limited to a scribe form or a matrix form, and may be patterned in various forms. The first scribing region S1 may be formed using a mechanical device or a laser device. For example, the first scribing area S1 may be formed by removing the first conductive layer 300 by irradiating a laser in one direction. The first scribing region S1 may be formed to have a width of 50 μm to 100 μm, for example. In addition, the first scribing region S1 may be formed to contact the dummy pattern 200 formed in the second scribing region S2, and may be formed at a predetermined interval from the dummy pattern 200. For example, it can form at intervals of 50 micrometers-100 micrometers.

Referring to FIG. 5, after the light absorbing layer 400 is formed on the whole including the dummy pattern 200 and the first conductive layer 300, the buffer layer 500 and the window layer 600 are formed on the light absorbing layer 400. To form.

The light absorbing layer 400 may be formed of, for example, an I-III-VI compound. That is, the light absorbing layer 400 is formed of a copper-indium-gallium-selenide (Cu (In, Ga) Se ₂ , CIGS) compound, or a copper-indium-selenide (CuInSe ₂ , CIS) compound or copper-gallium It can be formed of a selenide (CuGaSe ₂ , CGS) compound. The light absorbing layer 400 may be formed in various ways. For example, a CIG metal precursor film may be formed by sputtering using a copper target, an indium target, and a gallium target, or a mixed target of copper, indium, and gallium, respectively. After the formation, the selenization process may be performed using selenium (Se) at a high temperature to form the light absorbing layer 400 of the CIGS compound. In addition, the light absorbing layer 400 may form copper, indium, gallium, selenium (Cu, In, Ga, Se) by co-evaporation. Meanwhile, when the selenization process of the light absorbing layer 400 is performed, the metal elements constituting the first conductive layer 300 and the elements constituting the light absorbing layer 400 may be combined by mutual reaction. Accordingly, the intermetallic compound, that is, the alloy film 450 may be formed on the surface of the first conductive layer 300. For example, the alloy film 450 may be MoSe ₂ which is a compound of molybdenum (Mo) and selenium (Se). The alloy film 450 may be formed at an interface between the light absorbing layer 400 and the first conductive layer 300 to protect the surface of the first conductive layer 300. Meanwhile, since the alloy film 450 is not formed on the surface of the substrate 100 exposed through the first scribing region S1, the light absorbing layer 400 is formed inside the first scribing region S1. Can be gapfilled.

The buffer layer 500 may be formed of cadmium sulfide (CdS), for example, by chemical bath deposition (CBD). The window layer 600 may be formed of a transparent conductive material on the buffer layer 500. For example, the window layer 600 may be formed of any one of ITO, ZnO, and i-ZnO. The window layer 600 may be formed in various ways. For example, the window layer 600 may be formed of a ZnO layer by a sputtering process targeting ZnO, or a ZnO layer may be formed using a Zn target in an oxygen atmosphere. The buffer layer 500 and the window layer 600 are formed between the light absorbing layer 400 and the second conductive layer 700 to be formed later so that the light absorbing layer 400 and the second conductive layer 700 are well bonded. do.

Referring to FIG. 6, the window layer 600, the buffer layer 500, and the light absorbing layer 400 existing on the dummy pattern 200 are removed.

The light absorbing layer 400, the buffer layer 500, and the window layer 600 on the dummy pattern 200 may be removed using a mechanical device or a laser device. For example, the laser may be removed from the dummy pattern 200. It can be removed by irradiation in the forming direction. In this case, the window layer 600, the buffer layer 500, and the light absorbing layer 400 existing on the dummy pattern 200 may be removed to expose the first conductive layer 300 formed on the upper surface of the dummy pattern 200. Can be. Accordingly, the first conductive layer 300 is exposed on the upper surface of the dummy pattern 200, and the first conductive layer 300 and the light absorbing layer 400 are present on the side surfaces of the dummy pattern 200. In addition, the light absorbing layer 400, the buffer layer 500, and the window layer 600 exist in regions other than the dummy pattern 200. Therefore, the entire upper surface including the dummy pattern 200 is formed flat.

Referring to FIG. 7, a second conductive layer 700 is formed on the entire structure including the first conductive layer 300 and the window layer 600 on the dummy pattern 200.

The second conductive layer 700 is formed along the flat upper surface where the step is not generated. In addition, the second conductive layer 700 is electrically connected to the first conductive layer 300 on the upper surface of the dummy pattern 200, and the first conductive layer 300 is connected to the dummy pattern 200 from the upper surface of the dummy pattern 200. The first conductive layer 300, which is formed on the substrate 100 along the side surface of the substrate 100, is electrically connected to the second conductive layer 700 by the second conductive layer 700 to the first scribing region S1. Is connected. On the other hand, the second conductive layer 700 may be formed using a metal material such as aluminum. In addition, the second conductive layer 700 may be formed of a transparent conductive material to function as a transparent electrode on the front of the solar cell. The second conductive layer 700 may lower the resistance by doping aluminum or alumina to a transparent conductive material such as ZnO. On the other hand, the second conductive layer 700 may be formed by various methods, for example, by using a ZnO target by RF sputtering method, a reactive sputtering method using a Zn target, and an organometallic chemical vapor deposition method and the like. Can be formed. In addition, an indium tin oxide (ITO) thin film having excellent electro-optic properties may be deposited on the ZnO thin film to form a second conductive layer 700 having a dual structure.

Referring to FIG. 8, the third scribing region S3 is formed by removing predetermined regions of the second conductive layer 700, the window layer 600, the buffer layer 500, and the light absorbing layer 400.

The third scribing region S3 may be formed using a mechanical device or a laser device. For example, the third scribing area S3 may be formed by irradiating a laser in one direction. The third scribing region S3 may selectively expose the alloy layer 450. Meanwhile, the third scribing region S3 may be formed in the same shape as the first and second scribing regions S1 and S2. That is, the third scribing region S3 may be formed in a stripe shape in the same direction as the first and second scribing regions S1 and S2 or in various shapes including a matrix shape. The third scribing region S3 may be formed to be adjacent to the second scribing region S2. In addition, the third scribing region S3 is formed to have a width of 50 μm to 100 μm, for example, and the third scribing region S3 and the second scribing region S2 are 50 μm to 100 μm. It can be formed so as to maintain a spacing of μm. When the third scribing region S3 is formed, the surface of the first conductive layer 300 may be protected by the alloy film 450. That is, since the alloy film 450 is formed on the surface of the first conductive layer 300, the alloy film 450 serves as a protective layer of the first conductive layer 300, so that the third scribing region P3 is formed. It is possible to prevent the first conductive layer 300 from being damaged in the process of forming the film. The light absorbing layer 400, the buffer layer 500, the window layer 600, and the second conductive layer 700 may be separated by unit cells by the third scribe region P3. In this case, each cell may be connected to each other by the first conductive layer 300 formed on the dummy pattern 200. That is, the first conductive layer 300 and the second conductive layer 700 of adjacent cells may be physically and electrically connected to each other by the first conductive layer 300 formed on the dummy pattern 200.

As described above, in the method of manufacturing the solar cell according to the exemplary embodiment of the present invention, the dummy pattern 200 is formed in the second scribing region S2, and the substrate is formed along the side surface from the upper surface of the dummy pattern 200. The first scribing region S1 is formed after the first conductive layer 300 is formed on the substrate 100. Subsequently, the light absorbing layer 400, the buffer layer 500, and the window layer 600 are formed in the entire region including the dummy pattern 200, and then the layers on the dummy pattern 200 are removed to planarize the entire upper surface. do. Subsequently, after forming the second conductive layer 700 on the entire upper portion, the third scribing region S3 is formed. Therefore, since the second conductive layer 700 is formed on a flat surface where no step is generated, the problem of disconnection of the second conductive layer 700 does not occur, thereby improving efficiency and reliability of the solar cell. In addition, the first conductive layer 300 and the second conductive layer 700 of adjacent cells may be physically and electrically connected to each other by the first conductive layer 300 formed on the dummy pattern 200.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

100: substrate 200: dummy pattern
300: first conductive layer 400: light absorbing layer
500: buffer layer 600: window layer
700: second conductive layer 450: alloy film
S1: first scribe area S2: second scribe area
S3: third scribe area

Claims (14)

A dummy pattern formed in one region on the substrate;
A first conductive layer formed on the substrate and the dummy pattern;
A light absorbing layer formed on the first conductive layer on the substrate; And
And a second conductive layer formed on the light absorbing layer and the first conductive layer on the dummy pattern.
A dummy pattern formed in one region on the substrate;
A first conductive layer formed on the substrate along a side surface from an upper portion of the dummy pattern;
A light absorbing layer formed on the first conductive layer on the substrate; And
A second conductive layer formed on the light absorbing layer and the first conductive layer on the dummy pattern;
And the second conductive layer is connected to the dummy pattern side surface and the first conductive layer on the substrate through the first conductive layer on the dummy pattern.
The semiconductor device of claim 1, further comprising: a first scribing region provided by removing a predetermined region of the first conductive layer on the substrate;
A second scribing region spaced apart from the first scribing region by a predetermined distance; And
And a third scribing region provided by removing predetermined regions of the second conductive layer and the light absorbing layer.
The solar cell of claim 3, wherein the dummy pattern is formed on the second scribing region.
The solar cell of claim 3, wherein the third scribing region is at least partially overlapped with the dummy pattern.
The solar cell of claim 4, wherein the dummy pattern is formed of an insulating material.
The solar cell of claim 6, wherein at least one side surface of the dummy pattern is inclined.
The solar cell of claim 7, wherein the dummy pattern has a flat upper surface in consideration of thicknesses of the first conductive layer and the light absorbing layer.
The solar cell of claim 1, further comprising a buffer layer and a window layer formed on the light absorbing layer.
Forming a dummy pattern in one region on the substrate;
Forming a first conductive layer on the substrate and the dummy pattern;
Removing the light absorbing layer remaining on the dummy pattern after forming the light absorbing layer on the first conductive layer; And
Forming a second conductive layer on the light absorbing layer and the first conductive layer on the dummy pattern.
The method of claim 10, further comprising: removing a predetermined region of the first conductive layer on the substrate from one side of the dummy pattern to form a first scribing region; And
And removing a predetermined region of the second conductive layer and the light absorbing layer to be spaced apart from the other side of the dummy pattern by a predetermined interval to form a third scribing region.
The method of claim 10, further comprising: removing a predetermined region of the first conductive layer on the substrate from one side of the dummy pattern to form a first scribing region; And
And removing a predetermined region of the second conductive layer and the light absorbing layer to at least partially overlap the dummy pattern to form a third scribing region.
The method of claim 11, wherein the dummy pattern is formed using an insulating material.
The method of claim 13, wherein at least one side surface of the dummy pattern is inclined.

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