KR20150142414A - Thin Film Solar Cell Comprising P2 Patterning Part Applied Conductive Metal Layer and Method for Manufacturing the Same - Google Patents

Abstract

The present invention relates to a thin film solar cell and a manufacturing method thereof, which comprises: a substrate; a back electrode layer formed on the substrate; a first patterning part having a structure of an engraved fine line on some of the back electrode layer; a light absorption layer formed on the back electrode layer to have p-type conductivity; a window layer of a transparent electrode to have n-type conductivity unlike the light absorption layer; a buffer layer formed on an interface between the light absorption layer and the window layer; a conductive metal layer formed on the window layer in a shape of a line in order to correspond to a following second patterning part; the second patterning part formed by completely melting the conductive metal layer along with some parts of the light absorption layer, the buffer layer, and the window layer, which correspond to the conductive metal layer and then solidifying the melted part; and a third patterning part having a structure of an engraved fine line which infiltrates into the buffer layer and the window layer or into the light absorption layer, the buffer layer and the window layer.

Description

[0001] The present invention relates to a thin film solar cell including a P2 patterning portion to which a conductive metal layer is applied, and a method of manufacturing the thin film solar cell.

The present invention relates to a thin film solar cell including a P2 patterning portion to which a conductive metal layer is applied, and a manufacturing method thereof.

In recent years, in order to solve the energy problems faced, various researches have been conducted on alternative energy sources that can replace existing fossil fuels. In particular, extensive research is underway to utilize natural energy such as wind, nuclear, and solar power to replace petroleum resources that will be depleted within decades.

Among them, solar cells, which are photoelectric elements capable of converting solar energy into electrical energy, are infinite and environmentally friendly, unlike other energy sources, and have been attracting much attention since the development of Se solar cells in 1983.

Solar cell or photovoltaic cell is a core element of solar power generation that converts sunlight directly into electricity. Depending on its constituent materials, inorganic solar cell such as silicon or compound semiconductor, It can be classified into an organic solar cell including an organic material. Among them, as the thin film solar cell has a I-III-VI2 group knife kopayi light (Chalcopyrite) based compound semiconductor is a direct transition type energy band gap which is represented by CuInSe ₂ (CIS), a light absorption coefficient in the semiconductor 1x105cm ^-1 , It is possible to manufacture a solar cell with high efficiency even with a thin film having a thickness of 1 to 2 占 퐉, and also has excellent electro-optical stability over a long period of time. Therefore, it is being considered as a low-cost, high-efficiency solar cell material that can dramatically improve the economical efficiency of solar power generation by replacing the expensive crystalline silicon solar cell currently in use.

In order to obtain a predetermined voltage in the manufacture of such a solar cell module, it is necessary to electrically connect a predetermined number of solar cell units, which are basic unit units, by dividing a plurality of solar cell cells on the substrate by a patterning process And a manufacturing method of forming an integrated structure in which these are electrically connected is adopted.

This patterning process is composed of three patterning processes P1, P2, and P3. In the patterning P1, a rear electrode layer such as molybdenum is formed on an insulating substrate by a sputtering method, and then the rear electrode layer is divided into strips using a beam of an infrared region (1064 nm) such as a neodymium YAG laser. A p-type light absorption layer made of an I-III-VI2 family chalcopyrite semiconductor is formed thereon by a co-evaporation method or a selenization method, and then a buffer layer made of a transparent and highly resistive compound semiconductor thin film is formed by chemical growth from a solution To form a semiconductor thin film of a laminated structure. In the patterning P2, a semiconductor thin film, that is, a portion of the buffer layer and the p-type light absorbing layer is removed by a mechanical scribing method or a laser scribing method, and is then divided into strips and cut. The patterning P 2 is patterned by taking a positional offset in the same number as the number of unit cells divided and divided at the patterning P 1. In patterning P3, a window layer of a transparent electrode made of a metal oxide semiconductor thin film is formed on a buffer layer, and then a window layer, a buffer layer and a part of a p-type light absorbing layer of a transparent electrode are patterned by mechanical scribing or laser scribing By offsetting and mechanically removing it from its position in the strip. As a result, a solar cell having a stacked structure in which a p-type light absorbing layer, a buffer layer, and a window layer of a transparent electrode are stacked in this order on the back electrode layer is divided into cell units and the window layer of the transparent electrode of such solar cell is connected to the adjacent solar cell And is electrically connected to the back electrode layer. The structure of the thus-fabricated thin film solar cell is shown in FIG.

However, since the patterning process is spatially separated and performed under an atmospheric condition, the fabrication process is complicated. In the course of forming the window layer of the transparent electrode, the residual particles Or the vacuum process, and the process of taking out from the vacuum process are frequently performed, there is a high possibility that a defective phenomenon occurs due to contaminants interposed between the layers of the solar cell.

Thus, as an improved method, it is possible to form the window layer of the transparent electrode after the formation of the light absorption layer and the buffer layer, or additionally, the scribing process after the formation of the insulating layer, and then perform the laser annealing to the P2 position, A method of forming a conductive region at the P2 position through inter-mixing between the window layers of the substrate is proposed.

However, in the above method, laser irradiation conditions are required to be severe for mutual mixing of the window layer and the lower layer of the transparent electrode, and there is a high possibility that the thin film layer around the P2 pattern and the electric short-circuit are likely to occur.

Therefore, there is a high need for a technique for a solar cell that can solve the above problems.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

The inventors of the present application have conducted intensive research and various experiments and have found that in manufacturing a thin film solar cell, after forming all the constituent layers of a solar cell, a linear conductive metal layer is further formed so as to correspond to the second patterning portion And the second patterning portion is formed by laser annealing the portion where the conductive metal layer is formed, it is confirmed that the manufacturing cost and efficiency in the manufacturing process can be improved and the electrical conductivity can be increased while reducing the manufacturing defect rate of the second patterning portion , Thereby completing the present invention.

Therefore, in the thin film solar cell according to the present invention,

Board;

A back electrode layer formed on the substrate;

A first patterning part having a structure in which a part of the back electrode layer is removed in the form of fine lines;

A light absorbing layer formed on the back electrode layer and having a p-type conductivity;

A window layer of a transparent electrode having an n-type conductivity opposite to the light absorption layer;

A buffer layer formed at an interface between the light absorption layer and the window layer;

A light absorbing layer, a buffer layer, and a window layer corresponding to a portion where the conductive metal layer is formed are formed by laminating a conductive metal layer formed on the window layer in a linear shape corresponding to the second patterning portion, A second patterning portion;

A third patterning portion having a structure in which the buffer layer and the window layer, or a part of the light absorption layer, the buffer layer, and the window layer are removed in the form of fine lines; And

And a control unit.

As the main structure of the above structure, if it is a structure including the second patterning portion solidified after melting together with the conductive metal layer, it may further include a structure generally applicable to the solar cell, for example, an insulating layer Of course.

The method of fabricating the thin film solar cell of the above structure is not limited as long as the resulting structure is in the above-described constitutional range, but in one specific example,

Forming a back electrode layer on a substrate;

A first patterning process of removing a part of the back electrode layer in a fine line shape and patterning the same;

Forming a light absorbing layer having a p-type conductivity on the back electrode layer;

Forming a buffer layer on the light absorption layer;

Forming a window layer of a transparent electrode having an n-type conductivity type opposite to the light absorption layer on the buffer layer;

Forming a conductive metal layer in a line shape corresponding to the second patterning portion at a position where the second patterning portion is to be formed on the window layer;

A second patterning step of irradiating a laser beam at a position where the conductive metal layer is formed to solidify the light absorbing layer, the buffer layer, the window layer, and the conductive metal layer of the corresponding part, And

A third patterning step of removing and patterning the buffer layer and the window layer, or a part of the light absorption layer, the buffer layer, and the window layer in the form of fine lines;

. ≪ / RTI >

That is, in the thin film solar cell of the present invention, unlike the conventional method of forming the second patterning portion, after forming all of the constituent layers of the solar cell, a linear conductive metal layer is further formed to correspond to the second patterning portion, As described above, when the second patterning portion is formed by the conventional mechanical or laser scribing method, the defect rate due to the residual particles or contaminants, which is generated by laser annealing the portion where the conductive metal layer is formed, The second patterning process and the third patterning process can be continuously performed after the formation of all of the layers, so that the efficiency of the manufacturing process can be improved.

In one specific example, the conductive metal layer may contain at least one of the metal elements of the conductive metal elements, for example from the group consisting of Al, Ag, Cu, Ni, Mg, Au, And may contain one or more selected elements.

Such a conductive metal layer can be formed by E-beam evaporation, sputtering, ink coating, or printing, and in order to exhibit a desired degree of conductivity, May be formed to a thickness of 1 micrometer to 100 micrometers, in particular, 1 micrometer to 20 micrometers, and may be formed to have an aspect ratio of 0.1 to 1, . Here, the thickness means the length in the stacking direction of the layers constituting the solar cell, and the width means the length in the vertical direction in the stacking direction.

If the line width is less than 1 micrometer or the ratio of thickness to width is less than 0.1, the metal mixing effect can not be attained to the desired degree and the improvement of the conductivity is limited. When the line width exceeds 100 micrometers Or the ratio of the thickness to the width exceeds 1, it is not preferable because excessive energy is required to give a mixing effect by laser annealing.

When the light-absorbing layer, the buffer layer, and the window layer corresponding to the portion where the conductive metal layer is formed together with the conductive metal layer are formed by firing a point-like beam on the portion after the conductive metal layer is formed, compared with the case where the conductive metal layer is not formed , The metal mixing effect can be exhibited, and it is possible to melt even under low power or long wavelength because of high thermal conductivity, so that the cost of the laser annealing process can be greatly reduced, and the metal is contained in the second patterning portion, There is an effect that can show the conductivity.

Specifically, the laser beam may have a laser energy density of 1 mJ / cm ² to 1000 mJ / cm ² and may have a pulse duration of 1 ns to 100 ns.

This is comparable to using a laser beam having a laser energy density of 100 mJ / cm ² to 1 * 10 ⁴ mJ / cm ^{2 and} a pulse duration of 1 ns to 100 ns for conventional laser annealing The second patterning portion can be formed at a lower power than in the case of the structure according to the present invention.

The first patterning portion and the third patterning portion may be formed by a laser or a mechanical scribing method, unlike the second patterning portion. In detail, the first patterning portion and the third patterning portion may be formed by laser scribing Method, and the third patterning portion may be formed by a laser or a mechanical scribing method. For example, when the back electrode layer is Mo, the first patterning portion can be formed by 1064 nm DPSS, a fiber laser, or the like.

Generally, the patterning portion in the solar cell can increase the active region and improve the cell efficiency as the width of the removed portion becomes narrower. Therefore, the first to third patterning portions may be generally cut to a width of 5 to 1000 탆, and more specifically, may have a range of 10 to 150 탆.

In the case of the third patterning part, both the light absorbing layer, the buffer layer, and the window layer may be removed in a linear form as described above. Alternatively, only the buffer layer and the window layer may be formed in a fine line shape. In the case where only the buffer layer and the window layer are formed as described above, it is more preferable that the back electrode layer can be protected from scratch or corrosion due to exposure of the back electrode layer.

Hereinafter, other configurations of the solar cell will be described.

The substrate may be a glass substrate, a polymer substrate, a ceramic substrate, or a metal substrate. Specifically, a glass substrate may be used. For example, Corning 7059, Pyrex glass, or Sodalime glass Can be used.

Such a substrate can be nodularly flexible depending on the use, and a flexible solar cell can be manufactured according to the degree of flexibility, and utilization of the solar cell can be enhanced.

The back electrode layer formed on the substrate may be any metal generally used as an electrode. More specifically, the back electrode layer may include any one selected from the group consisting of Mo, Ni, Au, and Cu. Specifically, Mo, which can maintain a high conductivity, an ohmic contact with a compound used in a light absorbing layer, and a high temperature stability under a Se atmosphere, can be used. The back electrode layer may be formed to a thickness of 0.5 micrometers to 2 micrometers by electron beam (Beam) deposition, resistance heating deposition, or sputtering.

The light absorbing layer is formed on the back electrode layer and may be formed by co-evaporation, sputtering, electrodeposition, metal organic chemical vapor deposition (MOCVD), or ink coating using compound particles. Lt; RTI ID = 0.0 > micrometer. ≪ / RTI >

The light absorbing layer should contain Group I elements, Group III elements and Group VI elements, which may be added during the heat treatment step. The light absorbing layer thus formed may contain a compound represented by the following general formula (1) or (2).

Cu (In _x Ga _1-x ) (Se _y S _1-y ) ₂ (1)

Cu ₂ ZnSn (Se _z S _1-z ) ₄ (2)

In the above equations, 0 <x? 1, 0 <y? 1, 0 <z?

In forming the pn junction between the light absorbing layer having the p-type conductivity type and the window layer of the later-described two-sided conductive type having the conductive type, the buffer layer has a large difference in lattice constant and energy band gap between the two materials, In order to form a good junction between the layers. Therefore, it is preferable that the buffer layer is made of a material having a band gap in the middle of the two materials.

In detail, the buffer layer may include any one selected from the group consisting of ZnS, CdS, ZnSe, InS, InSe, InOOH, and ZnOOH, and may be selected from the group consisting of CdS, ZnSe, InS, InSe, InOOH, and ZnOOH Layer structure including a layer made of any one selected and an intrinsic ZnO layer. Here, the intrinsic zinc oxide layer can prevent the buffer layer from being damaged when the window layer is formed on the buffer layer by the sputtering method or the like.

The buffer layer may be formed to a thickness of 30 nanometers to 1.5 micrometers by CBD (Chemical Bath Deposition) or RF sputtering.

Finally, the window layer, which has an n-type conductivity and forms a p-n junction with the light absorption layer, functions as a transparent electrode on the entire surface of the solar cell, and therefore has high light transmittance and good electrical conductivity. More specifically, the window layer may include ZnO, which can ensure the transmittance of incoming sunlight by 80% or more, and may be formed into a double-layer structure including a ZnO layer and an ITO (Indium Tin Oxide) layer A low resistance value and a high light transmittance can be obtained.

The ZnO window layer can be formed by a method of depositing using a ZnO target by RF sputtering, a reactive sputtering method using Zn metal, or a metal organic chemical vapor deposition (MOCVD) As shown in FIG.

As described above, in the thin film solar cell according to the present invention, after forming all the constituent layers of the solar cell in the formation of the second patterning portion, a linear conductive metal layer is formed so as to correspond to the second patterning portion And the portion where the conductive metal layer is formed is laser annealed to reduce the defect rate of the second patterning portion as compared with the case where the second patterning portion is formed by the conventional mechanical or laser scribing method, The patterning process and the third patterning process can be continuously performed, thereby improving efficiency in the manufacturing process.

In addition, compared with the case where the conductive metal layer is not formed, the laser annealing conditions for mutual mixing can be relaxed by the metal mixing effect, so that the manufacturing cost can be remarkably lowered. In addition, There is an effect that can be.

1 is a cross-sectional view showing the structure of a conventional thin film solar cell;
FIGS. 2A to 2F are cross-sectional views illustrating a method of manufacturing a thin-film solar cell according to an embodiment of the present invention,
3 is a cross-sectional view illustrating the structure of a thin film solar cell according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. However, the present invention is not intended to be limited by the scope of the present invention.

FIGS. 2A to 2F are cross-sectional views illustrating a method of fabricating a thin film solar cell according to an embodiment of the present invention, showing a stacked structure according to process steps.

First, as shown in FIG. 2F, the thin film solar cell of the present invention includes a substrate 110; A back electrode layer 120 on the substrate 110; A first patterning part 170 having a structure in which a part of the back electrode layer 120 is removed in the form of fine lines; A light absorbing layer 130 formed on the back electrode layer 120 and having a p-type conductivity; A window layer 150 having a n-type conductivity opposite to the light absorption layer 130 and having a transparent electrode; A buffer layer 140 made of a transparent compound semiconductor thin film having high resistance and high resistance at the interface between the light absorption layer 130 and the window layer 150; The light absorbing layer 130, the buffer layer 140, and the window layer 150 corresponding to the portion where the conductive metal layer 160 is formed are completely melted by the laser beam A second patterning portion 180 in a post-solidified form; And a third patterning part 190 having a structure in which the light absorption layer 130, the buffer layer 140, and a part of the window layer 150 are removed in a fine line shape.

Next, a method of manufacturing the thin film solar cell having such a structure will be described in sequence.

2A, first, a substrate 110 made of insulating glass or the like is provided, and after cleaning the substrate 110, an electron beam (Beam) is deposited on the substrate 110, a resistance heating deposition method or a sputtering method is used Thereby forming a back electrode layer 120 made of a metal such as Mo or the like.

Referring to FIG. 2B, the back electrode layer 120 is divided into a strip shape by first patterning the back electrode layer 120 and forming the first patterning portion 170. The first patterning may use a laser scribing method.

2C, co-evaporation, sputtering, electrodeposition, metalorganic chemical vapor deposition (MOCVD), or chemical vapor deposition (CVD) may be performed on the back electrode layer 120 on which the first patterning portion 170 is formed. A light absorbing layer 130 containing a group I element, a group III element, and a group VI element and having a p-type conductivity is formed by an ink coating method using particles. At this time, the Group VI element may be added by a heat treatment process (selenization or sulphiding process) by injecting the Group V element material in the heat treatment step. The temperature of the heat treatment is preferably in the range of 350 ° C to 550 ° C. When the temperature of the heat treatment is less than 350 degrees Celsius, the light absorption layer 130 may not be crystallized. When the temperature of the heat treatment exceeds 550 degrees Celsius, the temperature is unnecessarily high for crystallizing the light absorption layer 130. Therefore, It is not preferable from the viewpoint of cost.

Thereafter, a buffer layer 140 made of a compound semiconductor thin film having high transparency and high resistance is formed on the light absorbing layer 130 by a chemical bath deposition (CBD) method or an RF sputtering method, and a buffer layer 140 is formed on the buffer layer 140 by RF sputtering (ZnO) target, a reactive sputtering method using a Zn metal, or a metal organic chemical vapor deposition (MOCVD) method to form a pn junction with the light absorption layer 130 A window layer 150 of a transparent electrode having a conductive type is formed.

2D, an E-beam evaporation method, a sputtering method, an ink coating method, or the like is used to correspond to the second patterning part at a position where the second patterning part is to be formed on the window layer 150 A conductive metal layer 160 containing a metal element in a linear form is formed by printing. Since the conductive metal layer 160 is formed at the position where the second patterning portion is formed, the conductive metal layer 160 may be removed from the position of the first patterning portion 170 by the same number as the number of the first patterning portions 170 A proper offset is formed at the position where it is taken.

Referring to FIG. 2D, the second patterning portion 180 is formed by patterning a laser beam at a position where the conductive metal layer 160 is formed, thereby forming a second patterning portion 180 from the conductive metal layer 160 to the light absorption layer 130 It is divided into strips. The second patterning is performed by laser annealing to solidify the light absorbing layer 130, the buffer layer 140, and the window layer 150 corresponding to the portion where the conductive metal layer 160 is formed together with the conductive metal layer 160, Lt; / RTI &gt;

Finally, referring to FIG. 2F, after the second patterning, the third patterning portion 190 may be successively formed to form the third patterning portion 190, thereby dividing the light absorbing layer 130 to the window layer 150 of the transparent electrode. The third patterning may use laser or mechanical scribing. At this time, the third patterning unit 190 is formed at a position where a proper offset is taken from the positions of the first patterning unit 170 and the second patterning unit 170. As a result, the solar cell 100 is divided into unit cell units, and the window layer 150 of one cell and the back electrode layer 120 of the neighboring cell are electrically connected.

When the second patterning portion is formed by further forming a line-shaped conductive metal layer corresponding to the second patterning portion after forming all the constituent layers of the solar cell and laser annealing the portion where the conductive metal layer is formed, The defective rate of the second patterning portion can be reduced and the second patterning process and the third patterning process can be continuously performed as compared with the case where the second patterning portion is formed by the mechanical or laser scribing method. There is an effect that can be improved.

In addition, compared with the case where the conductive metal layer is not formed, the laser annealing conditions for mutual mixing can be relaxed by the metal mixing effect, so that the manufacturing cost can be remarkably lowered. In addition, There is an effect that can be.

FIG. 3 shows a structure of a thin film solar cell according to another embodiment of the present invention.

3, a substrate 210, a rear electrode layer 220, a light absorption layer 230, a buffer layer 240, a window layer 250 of a transparent electrode, The second patterning part 280 may be formed of a conductive metal layer 260 and a conductive metal layer 260 formed on the first patterning part 270. The second patterning part 280 may include a first patterning part 270, a second patterning part 280 and a third patterning part 290, The buffer layer 240 and the window layer 250 corresponding to the first patterning portion 190 are completely melted and solidified after being completely melted by the laser beam but the third patterning portion 190 is formed in the light absorbing layer 230, Except that only the buffer layer 240 and the window layer 250 are removed in a fine line shape.

In the case where the buffer layer and the window layer are removed in this manner, the back electrode layer can be protected from scratch or corrosion due to the exposure of the back electrode layer.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (26)

Board;
A back electrode layer formed on the substrate;
A first patterning part having a structure in which a part of the back electrode layer is removed in the form of fine lines;
A light absorbing layer formed on the back electrode layer and having a p-type conductivity;
A window layer of a transparent electrode having an n-type conductivity opposite to the light absorption layer;
A buffer layer formed at an interface between the light absorption layer and the window layer;
A light absorbing layer, a buffer layer, and a window layer corresponding to a portion where the conductive metal layer is formed are formed by laminating a conductive metal layer formed on the window layer in a linear shape corresponding to the second patterning portion, A second patterning portion;
A third patterning portion having a structure in which the buffer layer and the window layer, or a part of the light absorption layer, the buffer layer, and the window layer are removed in the form of fine lines; And
Wherein the thin film solar cell comprises: The thin film solar cell according to claim 1, wherein the conductive metal layer contains at least one metallic element among conductive metallic elements. The thin film solar cell according to claim 2, wherein the conductive metal layer contains at least one element selected from the group consisting of Al, Ag, Cu, Ni, Mg, Au, Fe and In. The thin film solar cell according to claim 1, wherein the conductive metal layer is formed by E-beam evaporation, sputtering, ink coating, or printing. The thin film solar cell according to claim 1, wherein the line width of the conductive metal layer is from 1 micrometer to 100 micrometer. The thin film solar cell according to claim 5, wherein the line width of the conductive metal layer is 1 micrometer to 20 micrometer. The thin film solar cell according to claim 1, wherein the laser beam has a laser energy density of 1 mJ / cm ² to 1000 mJ / cm ² . The thin film solar cell according to claim 1, wherein the laser beam has a pulse duration of 1 ns to 100 ns. The thin film solar cell according to claim 1, wherein the first patterning portion is formed by a laser scribing method. The thin film solar cell according to claim 1, wherein the third patterning portion is formed by laser or mechanical scribing. The thin film solar cell according to claim 1, wherein the substrate is a glass substrate, a polymer substrate, a ceramic substrate, or a metal substrate. The thin film solar cell according to claim 1, wherein the back electrode layer comprises any one selected from the group consisting of Mo, Ni, Au, and Cu. 12. The thin film solar cell according to claim 11, wherein the back electrode layer is made of Mo. The thin film solar cell according to claim 1, wherein the light absorbing layer comprises a compound represented by the following formula (1) or (2).
Cu (In _x Ga _1-x ) (Se _y S _1-y ) ₂ (1)
Cu ₂ ZnSn (Se _z S _1-z ) ₄ (2)
In the above equations, 0 <x? 1, 0 <y? 1, 0 <z? The thin film solar cell according to claim 1, wherein the buffer layer comprises any one selected from the group consisting of ZnS, CdS, ZnSe, InS, InSe, InOOH and ZnOOH. The organic light emitting display according to claim 1, wherein the buffer layer is a double layer structure including a layer made of any one selected from the group consisting of ZnS, CdS, ZnSe, InS, InSe, InOOH and ZnOOH and intrinsic ZnO layers . The thin film solar cell according to claim 1, wherein the window layer comprises ZnO. The thin film solar cell according to claim 1, wherein the window layer is a double layer structure including a ZnO layer and an indium tin oxide (ITO) layer. Forming a back electrode layer on a substrate;
A first patterning process of removing a part of the back electrode layer in a fine line shape and patterning the same;
Forming a light absorbing layer having a p-type conductivity on the back electrode layer;
Forming a buffer layer on the light absorption layer;
Forming a window layer of a transparent electrode having an n-type conductivity type opposite to the light absorption layer on the buffer layer;
Forming a conductive metal layer in a line shape corresponding to the second patterning portion at a position where the second patterning portion is to be formed on the window layer;
A second patterning step of irradiating a laser beam at a position where the conductive metal layer is formed to solidify the light absorbing layer, the buffer layer, the window layer, and the conductive metal layer of the corresponding part, And
A third patterning step of removing and patterning the buffer layer and the window layer, or a part of the light absorption layer, the buffer layer, and the window layer in the form of fine lines;
The method of claim 1, The method according to claim 19, wherein the conductive metal layer contains at least one element selected from the group consisting of Al, Ag, Cu, Ni, Mg, Au, Fe and In. The method of manufacturing a thin film solar cell according to claim 19, wherein the conductive metal layer is formed by E-beam evaporation, sputtering, ink coating, or printing . 20. The method of claim 19, wherein the conductive metal layer is formed to a width of 1 micrometer to 100 micrometers. 20. The method of claim 19, wherein the laser beam has a laser energy density of 1 mJ / cm2 to 1000 mJ / cm2. 20. The method of claim 19, wherein the laser beam has a pulse duration of 1 ns to 100 ns. The method according to claim 19, wherein the first patterning portion is formed by a laser scribing method. 20. The method of claim 19, wherein the third patterning portion is formed by laser or mechanical scribing.

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