KR101363328B1 - Thin film type Solar Cell and Method for manufacturing the same - Google Patents

Abstract

The present invention relates to a substrate; A transparent electrode layer formed on the substrate; An auxiliary electrode layer formed on the transparent electrode layer; A semiconductor layer formed between the auxiliary electrode layers and on the auxiliary electrode layer; And a back electrode layer formed on the semiconductor layer, and a method of manufacturing the same.

According to the present invention, since the laser scribing process is not used, the substrate contamination problem caused by the particles generated by the conventional laser scribing process, the short circuit of the device, the problem of scribing unwanted parts, and the manufacturing process Since the problem of becoming complicated and a continuous process are not impossible, and the auxiliary electrode layer is formed on the transparent electrode layer, the thin film solar cell is separated by the auxiliary electrode layer even though the thin film solar cell is not separated into unit cells. The effect can be obtained, so that the resistance of the transparent electrode layer can be prevented from increasing even when faced.

Thin film solar cell, auxiliary electrode

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a thin film solar cell and a manufacturing method thereof,

The present invention relates to a thin film type solar cell, and more particularly, to a thin film type solar cell capable of minimizing a resistance of a front electrode.

Solar cells are devices that convert light energy into electrical energy using the properties of semiconductors.

The structure and principle of a solar cell will be briefly described. A solar cell has a PN junction structure in which a P (positive) semiconductor and an N (negative) semiconductor are bonded. When solar light enters the solar cell having such a structure, Holes and electrons are generated in the semiconductor due to the energy of the incident sunlight. At this time, the holes (+) move toward the P-type semiconductor due to the electric field generated at the PN junction, (-) is moved toward the N-type semiconductor to generate electric potential, thereby generating electric power.

Such a solar cell can be classified into a substrate type solar cell and a thin film type solar cell.

The substrate type solar cell is a solar cell manufactured using a semiconductor material itself such as silicon as a substrate, and the thin film type solar cell is formed by forming a semiconductor in the form of a thin film on a substrate such as glass to manufacture a solar cell.

Although the substrate type solar cell has a somewhat higher efficiency than the thin film type solar cell, there is a limitation in minimizing the thickness in the process, and a manufacturing cost is increased because an expensive semiconductor substrate is used.

Though the efficiency of the thin-film solar cell is somewhat lower than that of the substrate-type solar cell, the thin-film solar cell can be manufactured in a thin thickness and can be made of a low-cost material.

The thin-film solar cell is manufactured by forming a front electrode on a substrate such as glass, forming a semiconductor layer on the front electrode, and forming a rear electrode on the semiconductor layer. Here, since the front electrode forms a light receiving surface on which light is incident, a transparent conductive material such as ZnO is used as the front electrode.

However, as the substrate becomes larger in size, there arises a problem that the resistance of the front electrode made of the transparent conductive material is increased and the power loss is increased.

Accordingly, a method has been devised in which the thin film solar cell is divided into a plurality of unit cells and a plurality of unit cells are connected in series to minimize the resistance of the front electrode made of a transparent conductive material.

Hereinafter, a method of manufacturing a thin film solar cell having a plurality of unit cells connected in series will be described with reference to the drawings.

1A to 1F are cross-sectional views illustrating a conventional manufacturing process of a thin film solar cell having a plurality of unit cells connected in series.

First, as shown in FIG. 1A, a front electrode layer 12 is formed on a substrate 10 by using a transparent conductive material such as ZnO.

Next, as shown in FIG. 1B, the front electrode layer 12 is patterned to form the unit front electrodes 12a, 12b, and 12c. The patterning of the front electrode layer 12 is performed using a laser scribing process.

Next, as shown in FIG. 1C, a semiconductor layer 14 is formed on the entire surface of the substrate 10. The semiconductor layer 14 is formed using a semiconductor material such as silicon. The semiconductor layer 14 may be a P-type semiconductor layer (hereinafter, referred to as P layer), an I (intrinsic) (Hereinafter referred to as " N layer ") and an N (negative) semiconductor layer (hereinafter referred to as N layer).

1D, the semiconductor layer 14 is patterned to form the unit semiconductor layers 14a, 14b, and 14c. The patterning process of the semiconductor layer 14 is performed using a laser scribing process.

1E, a transparent conductive layer 16 and a rear electrode layer 18 are formed on the front surface of the substrate 10 in this order. ZnO is used for the transparent conductive layer 16, and Al is used for the rear electrode layer 18.

Next, as shown in FIG. 1F, the rear electrode layer 18 is patterned to form the unit rear electrodes 18a, 18b, and 18c. Here, when patterning the rear electrode layer 18, the transparent conductive layer 16 and the unit semiconductor layers 14b and 14c under the transparent conductive layer 16 are also patterned. The patterning process is performed using a laser scribing process.

As described above, in the related art, since the thin film solar cell is divided into a plurality of unit cells and a plurality of unit cells are connected in series, the power loss problem does not occur because the resistance of the front electrode is not increased even if the substrate is made large.

However, such a conventional thin-film solar cell essentially performs a laser scribing process in order to divide it into a plurality of unit cells. The following problems have arisen due to the laser scribing process.

First, when a laser scribing process is performed, a large amount of particles are generated, which causes contamination of the substrate. In addition, there is a problem that a device is short-circuited due to particles.

Second, the laser intensity and the exposure time can not be properly controlled during the laser scribing process, so that when the laser is over-irradiated, the lower layer of the layer to be scribed is scribed.

Third, there is a problem that the manufacturing process of the thin film solar cell is complicated by the laser scribing process itself. In addition, since the laser scribing process is generally performed in the atmospheric state, the process is performed in a different vacuum state and in a continuous process. There is a problem that cannot proceed.

The present invention has been devised to solve the problems of the conventional thin film type solar cell,

An object of the present invention is to provide a thin film solar cell capable of increasing the resistance of the front electrode without enlarging the area of the thin film solar cell by separating the thin film solar cell into a unit cell through a laser scribing process, and a manufacturing method thereof.

In order to achieve the above object, the present invention provides a semiconductor device comprising: a substrate; A transparent electrode layer formed on the substrate; An auxiliary electrode layer formed on the transparent electrode layer; A semiconductor layer formed between the auxiliary electrode layers and on the auxiliary electrode layer; And a rear electrode layer formed on the semiconductor layer.

An insulating layer may be further formed between the auxiliary electrode layer and the semiconductor layer.

The insulating layer may be formed to surround the top and side surfaces of the auxiliary electrode layer.

The insulating layer may be formed at a height higher than that of the auxiliary electrode layer on one side of the auxiliary electrode layer.

A transparent conductive layer may be additionally formed between the semiconductor layer and the rear electrode layer.

A first bus line connected to the auxiliary electrode layer, and a second bus line connected to the rear electrode layer may be additionally formed.

The first bus line is formed on one side of the substrate, the second bus line is formed on the other side of the substrate, and the insulating layer, the semiconductor layer, and the transparent conductive layer are not formed on the first bus line. .

The auxiliary electrode layer may include a plurality of first auxiliary electrode layers arranged in a first direction while maintaining a predetermined interval and a second auxiliary electrode layer arranged in a second direction while connecting each of the first auxiliary electrode layers.

The first and second directions may be perpendicular to each other, and the second auxiliary electrode layer may have a pattern for connecting one end of each of the first auxiliary electrode layers and a pattern for connecting the other ends of each of the first auxiliary electrode layers. A pattern connecting one end of each of the first auxiliary electrode layers and a pattern connecting the other end of each of the first auxiliary electrode layers may be alternately arranged.

The auxiliary electrode layer may further include a plurality of third auxiliary electrode layers intersecting with the first auxiliary electrode layers and arranged at predetermined intervals.

The back electrode layer may include a plurality of first back electrode layers arranged in a first direction while maintaining a predetermined gap, and a second back electrode layer connecting the first back electrode layers and arranged in a second direction.

The auxiliary electrode layer may be made of a material having a higher electrical conductivity than the transparent electrode layer.

The present invention also provides a method of manufacturing a semiconductor device, comprising: forming a transparent electrode layer on a substrate; Forming an auxiliary electrode layer on the transparent electrode layer; Forming a semiconductor layer between the auxiliary electrode layers and on the auxiliary electrode layer; And forming a back electrode layer on the semiconductor layer.

The method may further include forming an insulating layer between the forming of the auxiliary electrode layer and the forming of the semiconductor layer to surround the top and side surfaces of the auxiliary electrode layer.

Between the step of forming the auxiliary electrode layer and the step of forming the semiconductor layer, a step of forming an insulating layer at a height higher than the auxiliary electrode layer on one side of the auxiliary electrode layer may be further included.

Between the step of forming the transparent electrode layer and the step of forming the auxiliary electrode layer, a step of forming an insulating layer at a height higher than the auxiliary electrode layer on one side of the auxiliary electrode layer may be further included.

The method may further include forming a transparent conductive layer between the process of forming the semiconductor layer and the process of forming the back electrode layer.

The forming of the auxiliary electrode layer may include forming a first bus line connected to the auxiliary electrode layer.

The step of forming the insulating layer, the step of forming the semiconductor layer, and the step of forming the transparent conductive layer do not form respective layers on the first bus line.

The forming of the back electrode layer may include forming a second bus line connected to the back electrode layer.

The forming of the auxiliary electrode layer may include forming a plurality of first auxiliary electrode layers arranged in a first direction and second auxiliary electrode layers arranged in a second direction while connecting each of the first auxiliary electrode layers while maintaining a predetermined interval. It can be done in a process.

The step of forming the rear electrode layer includes forming a plurality of first rear electrode layers arranged in a first direction and a second rear electrode layer arranged in a second direction while connecting the first rear electrode layers while maintaining a predetermined gap therebetween Process.

According to the present invention as described above, the following effects can be obtained.

First, since the present invention does not use a laser scribing process, there are problems such as contamination of a substrate due to particles generated due to a laser scribing process, short circuit of a device, scribing of an undesired lower layer, The problem of becoming complicated, and the problem that the continuous process can not be performed do not occur.

Second, since the auxiliary electrode layer is formed on the transparent electrode layer, the thin film solar cell can be separated by the auxiliary electrode layer even though the thin film solar cell is not separated into unit cells. The resistance of is prevented from increasing.

Third, the present invention further forms an insulating layer between the auxiliary electrode layer and the semiconductor layer, thereby preventing defects that may occur at the interface between the auxiliary electrode layer and the semiconductor layer, and more clearly separating the thin film solar cell. It can enhance the light trapping effect.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

<Thin-film solar cell>

2 is a schematic cross-sectional view of a thin-film solar cell according to an embodiment of the present invention, Figures 3a to 3d is a plan view showing the auxiliary electrode layer of various forms constituting the thin-film solar cell according to the invention, Figure 4 FIG. 1 is a plan view illustrating a back electrode layer of one form constituting a thin film solar cell according to the embodiment. FIG.

2 is a cross-sectional view corresponding to line I-I of FIGS. 3A to 3D and FIG. 4.

As can be seen in Figure 2, the thin-film solar cell according to an embodiment of the present invention, the substrate 100, the transparent electrode layer 200, the auxiliary electrode layer 300, the semiconductor layer 400, the transparent conductive layer 500, and the back It comprises an electrode layer 600.

The substrate 100 may be made of glass or transparent plastic.

Transparent conductor such as F, or ITO (Indium Tin Oxide): the transparent electrode layer 200 is formed on the substrate (100), ZnO, ZnO: B, ZnO: Al, ZnO: H, SnO 2, SnO 2 The material can be formed by a sputtering method, a metal organic chemical vapor deposition (MOCVD) method, or the like.

Since the transparent electrode layer 200 is a surface on which solar light is incident, it is important to allow the incident sunlight to be absorbed to the inside of the solar cell as much as possible. For this purpose, the transparent electrode layer 200 may be textured. The surface may be formed of a bumpy concave-convex structure.

The texturing process is a process in which the material surface is formed into a rugged concavo-convex structure so as to be processed into the same shape as the surface of the fabric. An etching process using photolithography, anisotropic etching using a chemical solution, , Or a groove forming process using mechanical scribing, or the like. When such a texturing process is performed on the transparent electrode layer 200, the ratio of the incident sunlight to the outside of the solar cell is reduced, and the sunlight is scattered into the solar cell due to the scattering of incident sunlight. So that the efficiency of the solar cell is improved.

The auxiliary electrode layer 300 is formed on the transparent electrode layer 200 and serves to divide the thin film solar cell into a plurality of subcells. The auxiliary electrode layer 300 is formed to have a predetermined pattern without being formed on the entire upper portion of the transparent electrode layer 200. The predetermined pattern is made to be electrically connected.

The auxiliary electrode layer 300 may be formed in various patterns as shown in FIGS. 3A to 3D.

3A is a plan view showing one embodiment of the auxiliary electrode layer. The auxiliary electrode layer according to FIG. 3A includes a first auxiliary electrode layer 310 and a second auxiliary electrode layer 320a and 320b formed on the substrate 100. FIG.

The first auxiliary electrode layer 310 has a structure in which a plurality of first auxiliary electrode layers 310 are arranged in a first direction (for example, an up and down direction) while maintaining a predetermined interval, and the second auxiliary electrode layers 320a and 320b are formed of the first auxiliary electrode layer ( 310 is connected to each other to form a structure arranged in a second direction (for example, the left and right direction perpendicular to the first direction). In particular, the second auxiliary electrode layers 320a and 320b may have a pattern 320a connecting one end of each of the first auxiliary electrode layers 310 and a pattern 320b connecting the other end of each of the first auxiliary electrode layers 310. This is an alternating structure.

A first bus line 350 is connected to the auxiliary electrode layer 300.

The first bus line 350 serves to connect the thin film solar cell with an external circuit, and is formed on one side of the substrate 100 outside the active area A / A of the thin film solar cell.

Since the thin film solar cell is connected to an external circuit through the first bus line 350, any component is formed on the first bus line 350 to expose the first bus line 350 to the outside. (See Fig. 2).

FIG. 3B is a plan view showing another embodiment of the auxiliary electrode layer, and the auxiliary electrode layer according to FIG. 3B is the same as the auxiliary electrode layer according to FIG. 3A except that a third auxiliary electrode layer 330 is additionally formed.

The third auxiliary electrode layer 330 is formed to intersect with the first auxiliary electrode layer 310 and a plurality of the auxiliary electrode layers 330 are arranged at predetermined intervals.

As described above, the auxiliary electrode layer according to FIG. 3B further includes a third auxiliary electrode layer 330 to form a lattice structure as a whole, and thus the thin film solar cell is divided into more subdivided subcells.

3C is a plan view showing another embodiment of the auxiliary electrode layer, which is the same as the auxiliary electrode layer according to the above-described FIG. 3A except that the structure of the second auxiliary electrode layers 320c and 320d is different.

Referring to FIG. 3C, the second auxiliary electrode layers 320c and 320d form a pattern 320c connecting one end of all the first auxiliary electrode layers 310 and a pattern 320d connecting the other ends of both the first auxiliary electrode layers 310 ).

FIG. 3D is a plan view showing another embodiment of the auxiliary electrode layer, and the auxiliary electrode layer according to FIG. 3D is the same as the auxiliary electrode layer according to FIG. 3C except that the third auxiliary electrode layer 330 is additionally formed.

The third auxiliary electrode layer 330 crosses the first auxiliary electrode layer 310 and has a structure in which a plurality of third auxiliary electrode layers 330 are arranged at predetermined intervals.

As described above, the auxiliary electrode layer according to FIG. 3D is further configured with the third auxiliary electrode layer 330 to have a lattice structure as a whole, thereby dividing the thin film solar cell into subdivided subcells.

The auxiliary electrode layer 300 may be configured in various forms as shown in FIGS. 3A to 3D, but the auxiliary electrode layer 300 according to the present invention is not limited to the shape according to FIGS. 3A to 3D.

The auxiliary electrode layer 300 and the first bus line 350 connected thereto are Ag, Al, Ag + Al, Ag + Mg, Ag + Mn, Ag + Sb, Ag + Zn, Ag + Mo, Ag + Ni, Ag Metals such as + Cu, Ag + Al + Zn, etc. are formed by screen printing, inkjet printing, gravure printing or microcontact printing. can do.

The screen printing method is a method of forming a predetermined pattern by transferring a target material to a work using a screen and a squeeze. In the inkjet printing method, an object is sprayed onto a work using an inkjet, The gravure printing method is a method of applying a target material to a groove of a concave plate and transferring the target material to a workpiece again to form a predetermined pattern. The fine contact printing method is a method of forming a predetermined mold To form a target material pattern on a workpiece.

The auxiliary electrode layer 300 is preferably made of a material having a higher electrical conductivity than the transparent electrode layer 200 to minimize the problem of power loss due to an increase in the resistance of the transparent electrode layer 200.

The semiconductor layer 400 is formed between the auxiliary electrode layers 300 and on the auxiliary electrode layer 300.

The semiconductor layer 400 is not formed on the first bus line 350 to expose the first bus line 350 to the outside.

The semiconductor layer 400 may be formed of a semiconductor material, such as silicon, by plasma CVD, and the like, and the silicon-based semiconductor material may include amorphous silicon (a-Si: H) or microcrystalline silicon (μc-Si: H). ) Can be used.

The semiconductor layer 400 may have a PIN structure in which a P layer, an I layer, and an N layer are sequentially stacked. The semiconductor layer 400 generates holes and electrons by sunlight and the generated holes and electrons are collected in the P layer and the N layer, respectively, to improve the collection efficiency of such holes and electrons. For this purpose, a PIN structure is more preferable than a PN structure composed of only a P layer and an N layer.

When the semiconductor layer 400 is formed in the PIN structure as described above, the I layer is depleted by the P layer and the N layer to generate an electric field therein, and the holes and electrons generated by sunlight are The electric field drifts and is collected in the P and N layers, respectively.

On the other hand, when the semiconductor layer 400 is formed in a PIN structure, it is preferable to form the P layer first, and then form the I layer and the N layer in order, and the reason is generally the drift mobility of holes ( Since the drift mobility is low due to the drift mobility of the electrons, the P layer is formed close to the light receiving surface in order to maximize the collection efficiency by incident light.

The transparent conductive layer 500 is formed on the semiconductor layer 400.

The transparent conductive layer 500 is not formed on the first bus line 350 to expose the first bus line 350 to the outside.

The transparent conductive layer 500 may form a transparent conductive material such as ZnO, ZnO: B, ZnO: Al, ZnO: H, Ag by sputtering or metal organic chemical vapor deposition (MOCVD). have.

The transparent conductive layer 500 may be omitted, but it is preferable to form the transparent conductive layer 500 in order to increase efficiency of the solar cell. That is, when the transparent conductive layer 500 is formed, the sunlight passing through the semiconductor layer 400 passes through the transparent conductive layer 500 and progresses through various angles through scattering. This is because the ratio of light reflected and re-incident to the semiconductor layer 400 may be increased.

The back electrode layer 600 is not formed on the entire transparent conductive layer 500 but is formed to have a predetermined pattern, and the predetermined pattern is configured to be electrically connected.

As shown in FIG. 4, the back electrode layer 600 may include a first back electrode layer 610 and a second back electrode layers 620a and 620b formed on the substrate 100.

The first back electrode layer 610 has a structure in which a plurality of first back electrode layers 610 are arranged in a first direction (for example, an up and down direction) while maintaining a predetermined distance, and the second back electrode layers 620a and 620b are formed of the first back electrode layer ( 610 is connected to each other to form a structure arranged in a second direction (for example, the left and right direction perpendicular to the first direction). In particular, the second back electrode layers 620a and 620b may have a pattern 620a connecting one end of each of the first back electrode layers 610 and a pattern 620b connecting the other end of each of the first back electrode layers 610. This is an alternating structure.

In addition, a second bus line 650 is connected to the back electrode layer 600.

The second bus line 650 serves to connect the thin film solar cell with an external circuit together with the first bus line 350 described above. The second bus line 650 may be formed at an outer portion of the active area A / A of the thin film solar cell. It is formed on the other side of the substrate 100.

As such, the first bus line 350 is formed on one side of the substrate 100, and the second bus line 650 is formed on the other side of the substrate 100 to form a positive electrode and a thin film solar cell. It will form a negative pole.

4 illustrates one form of the back electrode layer 600 of the present invention, and the back electrode layer 600 according to the present invention is not limited to the form of FIG. 4.

The back electrode layer 600 and the second bus line 650 connected to the back electrode layer 600 may include Ag, Al, Ag + Al, Ag + Mg, Ag + Mn, Ag + Sb, Ag + Zn, Ag + Mo, Ag + Ni, Ag. Metals such as + Cu, Ag + Al + Zn and the like can be formed by screen printing, inkjet printing, gravure printing or microcontact printing. have.

FIG. 5 is a schematic cross-sectional view of a thin film solar cell according to another exemplary embodiment of the present invention, which is a cross-sectional view corresponding to lines I-I of FIGS. 3A to 3D and FIG. 4.

The thin film solar cell according to FIG. 5 is the same as the thin film solar cell according to FIG. 2 except that the insulating layer 700 is further formed. Therefore, the same reference numerals are assigned to the same components, and descriptions of the same components will be omitted.

The thin film solar cell according to FIG. 5 is characterized in that the insulating layer 700 is further formed, and the insulating layer 700 is formed to surround the top and side surfaces of the auxiliary electrode layer 300. Specifically, the insulating layer 700 is formed of the first auxiliary electrode layer 310, the second auxiliary electrode layers 320a, 320b, 320c, and 320d, and the third auxiliary electrode layer 330 illustrated in FIGS. 3A to 3D. It is formed to surround the upper surface and the side.

The insulating layer 700 prevents the auxiliary electrode layer 300 from directly contacting the semiconductor layer 400 to prevent defects that may occur at the interface between the two insulating layers 700.

The insulating layer 700 may be further formed at an outer portion of the active area A / A of the thin film solar cell. In this case, the first bus line 350 may be exposed to the outside to expose the first bus line 350 to the outside. The insulating layer 700 is not formed on the 350.

The insulating layer 700 is _{SiO 2, TiO 2, SiN x} , SiON, or insulating material to a screen printing method such as a polymer (screen printing), ink jet printing method (inkjet printing), gravure printing (gravure printing) or fine It may be formed using microcontact printing.

6 is a schematic cross-sectional view of a thin film solar cell according to still another embodiment of the present invention, which is a cross-sectional view corresponding to lines I-I of FIGS. 3A to 3D and FIG. 4.

The thin film solar cell according to FIG. 6 is the same as the thin film solar cell according to FIG. 2 except that the insulating layer 700 is further formed. Therefore, the same reference numerals are assigned to the same components, and descriptions of the same components will be omitted.

The thin film solar cell according to FIG. 6 is characterized in that the insulating layer 700 is further formed. The insulating layer 700 has a height higher than that of the auxiliary electrode layer 300 at one side of the auxiliary electrode layer 300. Is formed. Specifically, the insulating layer 700 is formed at a height higher than that of the first auxiliary electrode layer 310 on one side of the first auxiliary electrode layer 310 illustrated in FIGS. 3A to 3D. The second auxiliary electrode layers 320a, 320b, 320c, and 320d and / or one side of the third auxiliary electrode layer 330 may be formed at a height higher than that of each layer.

The insulating layer 700 is formed at a height higher than that of the auxiliary electrode layer 300 at one side of the auxiliary electrode layer 300, and serves to more clearly separate the subcells of the thin film solar cell. It also serves to enhance the trapping effect of the light by being reflected or scattered by the insulating layer 700.

The insulating layer 700 may be further formed at an outer portion of the active area A / A of the thin film solar cell. In this case, the first bus line 350 may be exposed to the outside to expose the first bus line 350 to the outside. The insulating layer 700 is not formed on the 350.

According to another embodiment of the present invention, the insulating layer 700 applied to the thin film solar cell according to FIG. 5 and the insulating layer 700 applied to the thin film solar cell according to FIG. 6 may be simultaneously applied. That is, the thin film solar cell according to another embodiment of the present invention has an insulating layer 700 surrounding the top and side surfaces of the auxiliary electrode layer 300, and one side of the auxiliary electrode layer 300 than the auxiliary electrode layer 300. It is provided with an insulating layer 700 formed at a high height.

<Manufacturing Method of Thin Film Solar Cell>

The drawings cited in the following description correspond to the cross-sections of the I-I lines of FIGS. 3A-3D and 4.

7A to 7E are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to an embodiment of the present invention.

First, as shown in FIG. 7A, the transparent electrode layer 200 is formed on the substrate 100.

The substrate 100 may be made of glass or transparent plastic.

The transparent electrode layer 200 is ZnO, ZnO: B, ZnO: Al, ZnO: H, SnO 2, SnO 2: F, or ITO (Indium Tin Oxide) sputtered (Sputtering) a transparent conductive material such as a method or a MOCVD ( Metal Organic Chemical Vapor Deposition) method or the like.

The transparent electrode layer 200 can be formed into a rugged concavo-convex structure through a texturing process or the like. The texturing process includes an etching process using a photolithography process, an anisotropic etching process using a chemical solution, Anisotropic etching, or a groove forming process using mechanical scribing, or the like.

Next, as shown in FIG. 7B, the auxiliary electrode layer 300 is formed on the transparent electrode layer 200.

Simultaneously with the formation of the auxiliary electrode layer 300, a first bus line 350 connected to the auxiliary electrode layer 300 may be formed, wherein the auxiliary electrode layer 300 is an active region (A / A) of a thin film solar cell. The first bus line 350 is formed outside the active area A / A.

The auxiliary electrode layer 300 and the first bus line 350 connected to the auxiliary electrode layer 300 may be formed in the pattern shown in FIGS. 3A to 3D. As a concrete method of forming the auxiliary electrode layer 300, Ag, Al, Ag + A metal such as Ag + Mn, Ag + Sb, Ag + Zn, Ag + Mo, Ag + Ni, Ag + Cu, and Ag + Al + Zn may be used for screen printing, inkjet printing, Gravure printing or microcontact printing may be used.

Next, as shown in FIG. 7C, the semiconductor layer 400 is formed between the auxiliary electrode layers 300 and on the auxiliary electrode layer 300.

The semiconductor layer 400 may be formed in a PIN structure by sequentially stacking a P layer, an I layer, and an N layer using a semiconductor material such as silicon based on plasma CVD.

The semiconductor layer 400 is not formed on the first bus line 350. For this purpose, the P layer, the I layer, and the N layer can be stacked by plasma CVD method while the upper part of the first bus line 350 is masked by using a shadow mask or the like.

Next, as shown in FIG. 7D, the transparent conductive layer 500 is formed on the semiconductor layer 400.

The transparent conductive layer 500 may form a transparent conductive material such as ZnO, ZnO: B, ZnO: Al, ZnO: H, Ag by sputtering or metal organic chemical vapor deposition (MOCVD). have.

The transparent conductive layer 500 is not formed on the first bus line 350. For this, a transparent conductive layer may be formed by sputtering or MOCVD in a state where the upper part of the first bus line 350 is masked using a shadow mask or the like.

The transparent conductive layer 500 may be omitted.

Next, as can be seen in Figure 7e, by forming a back electrode layer 600 on the transparent conductive layer 500, the manufacturing of the thin film solar cell of the configuration as shown in FIG.

At the same time as the back electrode layer 600 is formed, a second bus line 650 connected to the back electrode layer 600 may be formed, wherein the back electrode layer 600 is an active region (A / A) of a thin film solar cell. The second bus line 650 is formed outside the active area A / A.

The back electrode layer 600 and the second bus line 650 connected to the back electrode layer 600 may be formed in the pattern shown in FIG. 4, and specific forming methods may be Ag, Al, Ag + Al, Ag + Mg, Ag + Mn. , Metals such as Ag + Sb, Ag + Zn, Ag + Mo, Ag + Ni, Ag + Cu, Ag + Al + Zn, etc. screen printing, inkjet printing, gravure printing ( gravure printing or microcontact printing.

7A to 7E may be manufactured by using a cluster type device or an in-line type device.

8A to 8F are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another exemplary embodiment of the present invention, except that the exemplary embodiment further includes a process of forming an insulating layer 700. It is the same as the manufacturing process according to FIGS. 7A to 7E. Therefore, the same reference numerals are assigned to the same components, and a detailed description of the same components will be omitted.

First, as shown in FIG. 8A, the transparent electrode layer 200 is formed on the substrate 100.

Next, as shown in FIG. 8B, the auxiliary electrode layer 300 and the first bus line 350 connected thereto are formed on the transparent electrode layer 200.

Next, as shown in FIG. 8C, an insulating layer 700 is formed to surround the top and side surfaces of the auxiliary electrode layer 300.

The insulating layer 700 may include upper surfaces of the first auxiliary electrode layer 310, the second auxiliary electrode layers 320a, 320b, 320c, and 320d, and the third auxiliary electrode layer 330 illustrated in FIGS. 3A to 3D. Form to surround the side.

The insulating layer 700 is _{SiO 2, TiO 2, SiN x} , SiON, or insulating material to a screen printing method such as a polymer (screen printing), ink jet printing method (inkjet printing), gravure printing (gravure printing) or fine It may be formed using microcontact printing.

The insulating layer 700 may be additionally formed at an outer portion of the active region A / A of the thin film solar cell. In this case, the insulating layer 700 is not formed on the first bus line 350.

Meanwhile, when the insulating layer 700 is formed in a pattern as shown in FIG. 8C, the thin film solar cell finally manufactured has the configuration as shown in FIG. 5, and assists the insulating layer 700 in the process of FIG. 8C. One side of the electrode layer 300 may be formed at a height higher than that of the auxiliary electrode layer 300. In this case, the finally manufactured thin film solar cell has the configuration as shown in FIG. 6.

Next, as shown in FIG. 8D, between the auxiliary electrode layer 300 and the upper portion of the auxiliary electrode layer 300, more specifically, between the insulating layer 700 surrounding the auxiliary electrode layer 300 and the insulating layer 700. The semiconductor layer 400 is formed thereon.

Next, as shown in FIG. 8E, a transparent conductive layer 500 is formed on the semiconductor layer 400.

Next, as can be seen in Figure 8f, by forming a back electrode layer 600 on the transparent conductive layer 500, the manufacturing of the thin film solar cell of the configuration as shown in FIG.

As described above, the solar cell manufactured according to FIGS. 8A to 8F may be manufactured by using a cluster type device or an in-line type device.

9A to 9F are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to still another embodiment of the present invention, except that the embodiment further includes a process of forming an insulating layer 700. It is the same as the manufacturing process according to Figs. 7A to 7E. Therefore, the same reference numerals are assigned to the same components, and a detailed description of the same components will be omitted.

First, as shown in FIG. 9A, the transparent electrode layer 200 is formed on the substrate 100.

Next, as shown in FIG. 9B, an insulating layer 700 is formed on the transparent electrode layer 200.

The insulating layer 700 is formed to be higher than the auxiliary electrode layer 300 at a position corresponding to one side of the auxiliary electrode layer 300 formed in the process of FIG. 9C to be described later. In particular, when the auxiliary electrode layer 300 is formed as shown in FIGS. 3A to 3D, the insulating layer 700 is higher than the first auxiliary electrode layer 310 at one side of the first auxiliary electrode layer 310. It may be formed at a height, and in some cases, may be formed at a height higher than each layer at one side of the second auxiliary electrode layers 320a, 320b, 320c, and 320d and / or the third auxiliary electrode layer 330.

The insulating layer 700 is _{SiO 2, TiO 2, SiN x} , SiON, or insulating material to a screen printing method such as a polymer (screen printing), ink jet printing method (inkjet printing), gravure printing (gravure printing) or fine It may be formed using microcontact printing.

The insulating layer 700 may be additionally formed at an outer portion of the active region A / A of the thin film solar cell. In this case, the insulating layer 700 is not formed on the first bus line 350.

Next, as shown in FIG. 9C, the auxiliary electrode layer 300 and the first bus line 350 connected thereto are formed on the transparent electrode layer 200.

The auxiliary electrode layer 300 is formed at a position corresponding to the other side surface of the insulating layer 700.

Next, as shown in FIG. 9D, a semiconductor layer 400 is formed between the auxiliary electrode layer 300 (or the insulating layer 700) and on the auxiliary electrode layer 300 (or the insulating layer 700).

Next, as shown in FIG. 9E, a transparent conductive layer 500 is formed on the semiconductor layer 400.

Next, as can be seen in Figure 9f, by forming a back electrode layer 600 on the transparent conductive layer 500, the manufacturing of the thin film solar cell of the configuration as shown in FIG.

The solar cell manufactured according to FIGS. 9A to 9F may be manufactured by using a cluster type device or an in-line type device.

Meanwhile, the present invention uses the process according to FIGS. 8A to 8F, or a combination of the process according to FIGS. 8A to 8F and the process according to FIGS. 9A to 9F, and is applied to the thin film solar cell according to FIG. 5. The thin film solar cell to which the layer 700 and the insulating layer 700 applied to the thin film solar cell according to FIG. 6 are simultaneously applied may be manufactured.

1A to 1F are cross-sectional views illustrating a conventional manufacturing process of a thin film solar cell having a plurality of unit cells connected in series.

2 is a schematic cross-sectional view of a thin film solar cell according to an embodiment of the present invention.

3A to 3D are plan views illustrating various types of auxiliary electrode layers constituting the thin film solar cell according to the present invention.

4 is a plan view showing a back electrode layer of one form constituting the thin film solar cell according to the present invention.

5 is a schematic cross-sectional view of a thin film solar cell according to another embodiment of the present invention.

6 is a schematic cross-sectional view of a thin film solar cell according to still another embodiment of the present invention.

7A to 7E are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to an embodiment of the present invention.

8A to 8F are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another exemplary embodiment of the present invention.

9A to 9F are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to still another embodiment of the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS OF THE DRAWINGS FIG.

100: substrate 200: transparent electrode layer

300: auxiliary electrode layer 310: first auxiliary electrode layer

320a, 320b, 320c, and 320d: a second auxiliary electrode layer

330: third auxiliary electrode layer 350: first bus line

400: semiconductor layer 500: transparent conductive layer

600: back electrode layer 610: first back electrode layer

620a and 620b: second rear electrode layer 650: second bus line

Claims (23)

Board; A transparent electrode layer formed on the front surface of the substrate; An auxiliary electrode layer formed on the transparent electrode layer; An insulating layer formed to surround the top and side surfaces of the auxiliary electrode layer; A semiconductor layer formed between the insulating layers and on the insulating layer; And It comprises a back electrode layer formed on the semiconductor layer, In this case, the auxiliary electrode layer is electrically connected to the thin film type solar cell, characterized in that formed in a predetermined pattern for dividing the solar cell into a plurality of subcells. Board; A transparent electrode layer formed on the front surface of the substrate; An auxiliary electrode layer formed on the transparent electrode layer; A semiconductor layer formed between the auxiliary electrode layers and on the auxiliary electrode layer; And A back electrode layer formed on the semiconductor layer; An insulating layer is further formed between the auxiliary electrode layer and the semiconductor layer, In this case, the auxiliary electrode layer is electrically connected to the thin film type solar cell, characterized in that formed in a predetermined pattern for dividing the solar cell into a plurality of subcells. delete 3. The method of claim 2, The insulating layer is a thin-film solar cell, characterized in that formed on the side of the auxiliary electrode layer higher than the auxiliary electrode layer. The method according to claim 1 or 2, And a transparent conductive layer is additionally formed between the semiconductor layer and the rear electrode layer. The method according to claim 1 or 2, A first bus line connected to the auxiliary electrode layer, and a second bus line connected to the rear electrode layer. The method according to claim 6, The first bus line is formed on one side of the substrate, the second bus line is formed on the other side of the substrate, and the insulating layer, the semiconductor layer, and the transparent conductive layer are not formed on the first bus line. Thin-film solar cell, characterized in that. The method according to claim 1 or 2, The auxiliary electrode layer may include a plurality of first auxiliary electrode layers arranged in a first direction while maintaining a predetermined interval, and a second auxiliary electrode layer arranged in a second direction while connecting the first auxiliary electrode layers, respectively. Solar cells. 9. The method of claim 8, The first direction and the second direction are perpendicular to each other, The second auxiliary electrode layer is a thin film solar cell comprising a pattern connecting one end of each of the first auxiliary electrode layer and a pattern connecting the other end of each of the first auxiliary electrode layer. 10. The method of claim 9, The thin film solar cell of claim 1, wherein a pattern connecting one end of each of the first auxiliary electrode layers and a pattern connecting another end of each of the first auxiliary electrode layers are alternately arranged. 10. The method of claim 9, The auxiliary electrode layer may further include a plurality of third auxiliary electrode layers intersecting with the first auxiliary electrode layers and arranged at predetermined intervals. The method according to claim 1 or 2, Wherein the back electrode layer comprises a plurality of first back electrode layers arranged in a first direction and a second back electrode layer arranged in a second direction while connecting the first back electrode layers while maintaining a predetermined gap therebetween, Solar cells. The method according to claim 1 or 2, The auxiliary electrode layer is a thin film solar cell, characterized in that made of a material having a higher electrical conductivity than the transparent electrode layer. delete delete delete delete delete delete delete delete delete delete

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