KR101397159B1 - Thin film type Solar Cell and Method for manufacturing the same - Google Patents

Abstract

The present invention provides a semiconductor device comprising: a substrate; An auxiliary electrode layer formed on the substrate; An insulating layer formed in a region between the auxiliary electrode layers on the substrate; A transparent electrode layer formed on the auxiliary electrode layer and the insulating layer; A semiconductor layer formed on the transparent electrode layer; And a rear electrode layer formed on the semiconductor layer, and a method of fabricating the thin film solar cell,

According to the present invention, since the laser scribing process is not used, problems such as contamination of the substrate due to the particles generated due to the laser scribing process, short circuit of the device, scribing of the undesired lower layer, And the problem that the continuous process can not be performed does not occur.

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.

In order to solve the problem caused by particles, it is possible to add a cleaning process after laser scribing process. In this case, since the cleaning process is added, the process becomes complicated and an additional cleaning device is needed, There is a problem of rising.

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, the manufacturing process of the thin film solar cell is complicated due to the laser scribing process itself. In addition, since the laser scribing process is generally performed in the atmospheric state, There is a problem in that it can not proceed to the next step.

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; An auxiliary electrode layer formed on the substrate; An insulating layer formed in a region between the auxiliary electrode layers on the substrate; A transparent electrode layer formed on the auxiliary electrode layer and the insulating layer; A semiconductor layer formed on the transparent electrode layer; And a rear electrode layer formed on the semiconductor layer.

In order to achieve the above object, the present invention also 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; An insulating layer formed in a region between the auxiliary electrode layers on the transparent electrode layer; A semiconductor layer formed on the auxiliary electrode layer and the insulating layer; And a rear electrode layer formed on the semiconductor layer.

The auxiliary electrode layer and the insulating layer may be alternately formed at regular intervals in one direction.

The insulating layer may have a height higher than that of the auxiliary electrode layer.

The insulating layer may have a structure in which a transparent insulating material having an elliptical horizontal section is spaced apart.

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 first bus line is exposed to the outside.

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

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 present invention also provides a method of manufacturing a plasma display panel, comprising the steps of: forming an insulating layer on an area between an auxiliary electrode layer and the auxiliary electrode layer on a substrate; Forming a transparent electrode layer on the auxiliary electrode layer and the insulating layer; Forming a semiconductor layer on the transparent electrode layer; And forming a rear electrode layer on the semiconductor layer. The present invention also provides a method of manufacturing a thin film solar cell.

The present invention also provides a method of manufacturing a semiconductor device, comprising: forming a transparent electrode layer on a substrate; Forming an insulating layer on an area between the auxiliary electrode layer and the auxiliary electrode layer on the transparent electrode layer; Forming a semiconductor layer on the auxiliary electrode layer and the insulating layer; And forming a rear electrode layer on the semiconductor layer. The present invention also provides a method of manufacturing a thin film solar cell.

The auxiliary electrode layer and the insulating layer may be alternately formed at a predetermined interval in one direction.

The step of forming the insulating layer may include a step of forming an insulating layer at a higher height than the auxiliary electrode layer.

The step of forming the insulating layer may include a step of forming a transparent insulating material having an elliptical horizontal cross section and spaced apart from each other.

And a step of forming a transparent conductive layer between the semiconductor layer and the rear electrode layer.

Wherein forming the auxiliary electrode layer includes forming a first bus line connected to the auxiliary electrode layer, and the step of forming the rear electrode layer includes forming a second bus line connected to the rear electrode layer . ≪ / RTI >

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

The auxiliary electrode layer may be formed by forming a plurality of first auxiliary electrode layers arranged in a first direction and a second auxiliary electrode layer connecting the first auxiliary electrode layers and arranged in a second direction while maintaining a predetermined gap therebetween 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 in contact with the transparent electrode layer, even if the thin-film solar cell is not separated into unit cells, the auxiliary electrode layer can separate the thin-film solar cell, The resistance of the electrode layer is prevented from increasing.

Third, the present invention has an effect of increasing the total area of the semiconductor layer by forming the insulating layer, thereby improving the efficiency of the solar cell, and enhancing the light absorption rate in the semiconductor layer by increasing the light trapping rate of the insulating layer .

Fourth, when the transparent electrode layer is formed on the auxiliary electrode layer and the insulating layer and the semiconductor layer is formed on the transparent electrode layer, the other structure is not formed between the transparent electrode layer and the semiconductor layer, have.

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

<Thin-film solar cell>

FIG. 2 is a schematic cross-sectional view of a thin film solar cell according to an embodiment of the present invention, FIGS. 3A to 3D are plan views showing various types of auxiliary electrode layers and insulating layers constituting the thin film solar cell according to the present invention, Is a plan view showing one type of the rear electrode layer constituting the thin film solar cell according to the present invention.

2 is a cross-sectional view corresponding to the line I-I in Figs. 3A to 3E. One

2, the thin film solar cell according to an embodiment of the present invention includes a substrate 100, a transparent electrode layer 200, an auxiliary electrode layer 300, an insulating layer 400, a semiconductor layer 500, (600), and a rear electrode layer (700).

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 sunlight is incident, it is important that the incident solar light is absorbed into the solar cell as much as possible. To this end, the transparent electrode layer 200 is subjected to a texturing process So that its surface can be formed into a rugged concavo-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 to divide the thin film solar cell into a plurality of sub-cells. The width and height of the auxiliary electrode layer 300 are preferably as small as possible, Can be improved.

The auxiliary electrode layer 300 is not formed on the entire upper surface of the transparent electrode layer 200 but has a predetermined pattern, and the predetermined pattern can 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 layers 310 and 320b are arranged in a first direction (for example, in a vertical direction) while maintaining a predetermined gap therebetween. The second auxiliary electrode layers 320a and 320b are formed in the first auxiliary electrode layer 310) are arranged in a second direction (for example, a left-right direction perpendicular to the first direction). Particularly, the second auxiliary electrode layers 320a and 320b may include a pattern 320a connecting one end of each of the first auxiliary electrode layers 310 and a pattern 320b connecting the other ends of the first auxiliary electrode layers 310, Thereby forming a structure alternately arranged.

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

The first bus line 350 connects 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 the external circuit through the first bus line 350, no component is formed on the first bus line 350 to expose the first bus line 350 to the outside It does not.

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.

In this way, the auxiliary electrode layer according to FIG. 3B has a lattice structure as a whole by further constituting the third auxiliary electrode layer 330, so that the thin film solar cell is divided into sub-cells having a finer structure.

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 is formed to intersect with the second 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. 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 have various shapes as shown in FIGS. 3A to 3D, but the auxiliary electrode layer 300 according to the present invention is not limited to the shapes according to FIGS. 3A to 3D.

The auxiliary electrode layer 300 and the first bus line 350 connected thereto may be formed of Ag, Al, Ag + Al, Ag + Mg, Ag + Mn, Ag + Sb, Ag + Zn, Ag + A metal such as Cu, Ag + Al + Zn is formed by screen printing, inkjet printing, gravure printing or microcontact printing .

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 insulating layer 400 is patterned in a region between the auxiliary electrode layers 300 on the transparent electrode 200 and may be formed of SiO ₂ , TiO ₂ , SiN _x , SiON, And is made of the same transparent insulating material.

3A to 3D, it is preferable that the insulating layer 400 and the auxiliary electrode layer 300 are formed alternately in a predetermined direction (for example, left and right in FIGS. 3A to 3D) at regular intervals.

The first function of the insulating layer 400 is to increase the total area of the semiconductor layer 500 to improve the efficiency of the solar cell.

That is, when the insulating layer 400 is formed as compared with the case where the insulating layer 400 is not formed, the total area of the semiconductor layer 500 formed on the insulating layer 400 is increased, do. Therefore, the insulating layer 400 may be formed to have a higher height than the auxiliary electrode layer 300 to further increase the overall area of the semiconductor layer 500.

The second function of the insulating layer 400 is to enhance the light trapping rate.

That is, when the insulating layer 400 is formed, the light transmitted through the transparent electrode 200 under the transparent layer 200 is refracted and scattered at various angles in the insulating layer 400 to enhance the trapping effect of light, 500), the light absorption rate is increased.

As shown in FIGS. 3A to 3D, the insulating layer 400 having such a function is preferably made of a structure in which insulating materials having an elliptical horizontal section are spaced apart. Even if the insulating layer 400 is made of a transparent insulating material, if the horizontal cross section of the insulating layer 400 is enlarged, the light transmittance may be lowered. Therefore, the insulating layer 400 may be small Because it is preferable to form the film. The insulating layer 400 may have a structure in which insulators are linearly formed not in a structure in which insulators are spaced apart from each other between the auxiliary electrode layers 300, But may be a triangle, a polygon such as a rectangle, or a circle.

The insulating layer 400 may be formed using a screen printing method, an inkjet printing method, a gravure printing method, or a microcontact printing method.

The semiconductor layer 500 is formed on the auxiliary electrode layer 300, the insulating layer 400, and the transparent electrode layer 200.

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

The semiconductor layer 500 may be formed of amorphous silicon (a-Si: H) or microcrystalline silicon (μc-Si: H), for example, by a plasma CVD method or the like. ) Can be used.

The semiconductor layer 500 may have a PIN structure in which a P layer, an I layer, and an N layer are sequentially stacked. The semiconductor layer 500 generates holes and electrons by sunlight, and the generated holes and electrons are collected in the P layer and the N layer, respectively. In order to improve the collection efficiency of holes and electrons The PIN structure is more preferable than the PN structure composed only of the P layer and the N layer.

When the semiconductor layer 500 is formed in the PIN structure, the I layer is depleted by the P layer and the N layer, and an electric field is generated in the semiconductor layer 500. The holes and electrons generated by the sunlight And are drifted by the electric field to be collected in the P layer and the N layer, respectively.

On the other hand, when the semiconductor layer 500 is formed with a PIN structure, it is preferable to form the P layer first and then form the I layer and the N layer in order, because the drift mobility (drift mobility) is low due to the drift mobility of electrons, the P layer is formed close to the light receiving surface in order to maximize the collection efficiency by the incident light.

The transparent conductive layer 600 is formed on the semiconductor layer 500 and is not formed on the first bus line 350 to expose the first bus line 350 to the outside.

The transparent conductive layer 600 may be formed using a transparent conductive material such as ZnO, ZnO: B, ZnO: Al, ZnO: H, or Ag by a sputtering method or an MOCVD (Metal Organic Chemical Vapor Deposition) have.

Although the transparent conductive layer 600 may be omitted, it is preferable to form the transparent conductive layer 600 to improve the efficiency of the solar cell. That is, when the transparent conductive layer 600 is formed, the solar light transmitted through the semiconductor layer 500 passes through the transparent conductive layer 600 and diffuses at various angles through scattering, The ratio of the light reflected back to the semiconductor layer 500 may be increased.

The rear electrode layer 700 is formed on the transparent conductive layer 600.

The rear electrode layer 700 may be formed to have a predetermined pattern without being formed on the entire upper surface of the transparent conductive layer 600, and the predetermined pattern may be electrically connected.

The rear electrode layer 700 may be formed in an upper portion of the area between the auxiliary electrode layers 300, that is, above the region where the insulating layer 400 is formed. The reason why the rear electrode layer 700 is not formed on the auxiliary electrode layer 300 is that the area where the auxiliary electrode layer 300 is formed does not contribute to the cell efficiency, There is no need to form the rear electrode layer 700 and thus the cost of the paste for forming the rear electrode layer 700 is reduced. However, the rear electrode layer 700 may be formed on the auxiliary electrode layer 30.

The rear electrode layer 700 may include a first rear electrode layer 710 and a second rear electrode layer 720a and 720b formed on the substrate 100 as shown in FIG.

The first and second back electrode layers 720a and 720b are formed in a structure in which a plurality of first back electrode layers 710 are arranged in a first direction (e.g., a vertical direction) 710) are arranged in a second direction (for example, a left-right direction perpendicular to the first direction). Particularly, the second rear electrode layers 720a and 720b may include a pattern 720a connecting one end of each of the first rear electrode layers 710 and a pattern 720b connecting the other ends of the first rear electrode layers 710, Thereby forming a structure alternately arranged.

A second bus line 750 is connected to the rear electrode layer 700.

The second bus line 750 serves to connect the thin film solar cell with an external circuit together with the first bus line 350. The second bus line 750 is connected to the outside of the active area A / Is formed on the other side of the substrate (100).

The first bus line 350 is formed on one side of the substrate 100 and the second bus line 750 is formed on the other side of the substrate 100 to form a positive electrode and a negative electrode of the thin film solar cell, (-) pole.

3E shows one embodiment of the rear electrode layer 700 of the present invention. The rear electrode layer 700 according to the present invention is not limited to the embodiment according to FIG. 3E, And the like.

The rear electrode layer 700 and the second bus line 750 connected thereto may be formed of Ag, Al, Ag + Al, Ag + Mg, Ag + Mn, Ag + Sb, Ag + Zn, Ag + A metal such as Cu, Ag + Al + Zn can be formed by screen printing, inkjet printing, gravure printing, or microcontact printing. have.

4 is a schematic cross-sectional view of a thin-film solar cell according to another embodiment of the present invention, and is a cross-sectional view taken along line I-I of FIGS. 3A to 3E.

The thin film solar cell according to FIG. 4 is the same as the thin film solar cell according to FIG. 2 except for the formation position of the transparent electrode layer 200. Therefore, the same reference numerals are assigned to the same components, and a detailed description of the same components will be omitted.

4, the thin film solar cell according to another embodiment of the present invention includes a substrate 100, an auxiliary electrode layer 300, an insulating layer 400, a transparent electrode layer 200, a semiconductor layer 500, A conductive layer 600, and a rear electrode layer 700.

The auxiliary electrode layer 300 is formed on the substrate 100 in various patterns as shown in FIGS. 3A to 3D. A first bus line 350 is connected to the auxiliary electrode layer 300.

The insulating layer 400 may be formed on the substrate 100 between the auxiliary electrode layers 300 and may have a structure in which insulators having an elliptical horizontal section are spaced apart from each other as shown in FIGS. .

The transparent electrode layer 200 is formed on the substrate 100, the auxiliary electrode layer 300, and the insulating layer 400.

The semiconductor layer 500 is formed on the transparent electrode layer 200.

The rear electrode layer 700 may be formed on the semiconductor layer 500 in a pattern shown in FIG. 3E. A second bus line 750 is connected to the rear electrode layer 700.

4, the transparent electrode layer 200 is formed on the auxiliary electrode layer 300 and the insulating layer 400 so that the transparent electrode layer 200 is formed on the substrate 100, Type solar cell according to the present invention. 4, the transparent electrode layer 200 is formed directly under the semiconductor layer 500, so that an insulating layer 400 is formed between the transparent electrode layer 200 and the semiconductor layer 500 The efficiency of the battery can be improved compared with the thin film solar cell of FIG. 2 in which the insulating layer 400 is formed between the transparent electrode layer 200 and the semiconductor layer 500. [

<Manufacturing Method of Thin Film Solar Cell>

The drawings cited in the following description correspond to the cross section of the line I-I in Figs. 3A to 3E.

5A to 5E are cross-sectional views illustrating a manufacturing process of a thin-film solar cell according to an embodiment of the present invention, which is a process for manufacturing the thin-film solar cell according to the above-described FIG.

5 (a), a transparent electrode layer 200 is formed on a 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. 5B, an auxiliary electrode layer 300 and an insulating layer 400 are formed on the transparent electrode layer 200.

The auxiliary electrode layer 300 may be formed first and then the insulating layer 400 may be formed first and then the auxiliary electrode layer 300 may be formed.

The insulating layer 400 and the auxiliary electrode layer 300 may be alternately formed at a predetermined interval in one direction.

The auxiliary electrode layer 300 may be formed on the first bus line 350 connected to the auxiliary electrode layer 300 at the same time as the auxiliary electrode layer 300. In this case, Is formed in the active area A / A and 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.

The insulating layer 400 may be formed using a transparent insulating material such as SiO ₂ , TiO ₂ , SiN _x , SiON, or a polymer in a region between the auxiliary electrode layers 300. Screen printing, inkjet printing, gravure printing, or microcontact printing may be used.

The insulating layer 400 may have a height higher than that of the auxiliary electrode layer 300, and may have an elliptical horizontal cross-section as shown in FIGS. 3A to 3D.

Next, as shown in FIG. 5C, the semiconductor layer 500 is formed on the auxiliary electrode layer 300 and the insulating layer 400.

The semiconductor layer 500 may be formed in a PIN structure by sequentially laminating a P layer, an I layer, and an N layer on a semiconductor material such as a silicon based material by a plasma CVD method or the like.

The semiconductor layer 500 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. 5D, a transparent conductive layer 600 is formed on the semiconductor layer 500.

The transparent conductive layer 600 may be formed using a transparent conductive material such as ZnO, ZnO: B, ZnO: Al, ZnO: H, or Ag by a sputtering method or an MOCVD (Metal Organic Chemical Vapor Deposition) have.

The transparent conductive layer 600 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 600 may be omitted

5E, a rear electrode layer 700 is formed on the transparent conductive layer 600 to complete the manufacture of the thin film solar cell having the structure shown in FIG.

The rear electrode layer 700 may be formed in an upper portion of the area between the auxiliary electrode layers 300, that is, above the region where the insulating layer 400 is formed. However, the rear electrode layer 700 may be formed on the auxiliary electrode layer 300.

A second bus line 750 is formed on the rear electrode layer 700 and connected to the rear electrode layer 700 at the same time as the rear electrode layer 700. The rear electrode layer 700 may be a thin film solar cell, And the second bus line 750 is formed in the outside of the active area A / A.

The rear electrode layer 700 and the second bus line 750 connected thereto may be formed in the pattern shown in FIG. 3E, and a specific method of forming the rear electrode layer 700 may be Ag, Al, Ag + Al, Ag + Mg, Ag + A metal such as Ag + Sb, Ag + Zn, Ag + Mo, Ag + Ni, Ag + Cu and Ag + Al + Zn is applied by screen printing, inkjet printing, gravure printing or microcontact printing may be used.

The solar cell manufactured according to the above-described FIGS. 5A to 5E can be manufactured using a cluster type device or an in-line type device.

6A to 6E are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another embodiment of the present invention, which is a manufacturing process of the thin film solar cell according to the above-described FIG.

6A to 6E are the same as the manufacturing process according to FIGS. 5A to 5E except for the formation position of the transparent electrode layer 200, and thus a detailed description of the same constitution will be omitted.

First, as shown in FIG. 6A, an auxiliary electrode layer 300 and an insulating layer 400 are formed on a substrate 100.

The auxiliary electrode layer 300 may be formed first and then the insulating layer 400 may be formed first and then the auxiliary electrode layer 300 may be formed.

A first bus line 350 connected to the auxiliary electrode layer 300 and the auxiliary electrode layer 300 is formed at the same time as the auxiliary electrode layer 300 is formed.

The insulating layer 400 may be formed in a region between the auxiliary electrode layers 300 and may have a height higher than the auxiliary electrode layer 300.

6B, a transparent electrode layer 200 is formed on the substrate 100, the auxiliary electrode layer 300, and the insulating layer 400. Next, as shown in FIG.

The transparent electrode layer 200 can be formed into a rugged concavo-convex structure through a texturing process or the like.

Next, as shown in FIG. 6C, the semiconductor layer 500 is formed on the transparent electrode layer 200.

The semiconductor layer 500 is not formed on the first bus line 350. For this purpose, the upper part of the first bus line 350 is masked by using a shadow mask, Method is used to form a semiconductor layer.

Next, as shown in FIG. 6D, a transparent conductive layer 600 is formed on the semiconductor layer 500.

6E, a rear electrode layer 700 is formed on the transparent conductive layer 600 to complete the manufacture of the thin film solar cell having the structure shown in FIG.

A second bus line 750 is formed at the same time as the rear electrode layer 700 and connected to the rear electrode layer 700 when the rear electrode layer 700 is formed.

7A to 7E can be performed in a continuous process through a cluster type equipment or an in-line type equipment.

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.

FIGS. 3A to 3D are plan views showing various types of auxiliary electrode layers and insulating layers constituting the thin film solar cell according to the present invention. FIG. 3E is a plan view showing one embodiment of a back electrode layer constituting the thin film solar cell according to the present invention. to be.

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

5A to 5E are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to an embodiment of the present invention.

6A to 6E are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to 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: insulating layer 500: semiconductor layer

600: transparent conductive layer 700: rear electrode layer

710: first rear electrode layer 720a, 720b: second rear electrode layer 750: second bus line

Claims (20)

Board; An auxiliary electrode layer formed on an upper surface of the substrate; An insulating layer formed in a region between the auxiliary electrode layers on an upper surface of the substrate; A transparent electrode layer formed on the upper surface of the auxiliary electrode layer, the upper surface of the insulating layer, and the upper surface of the substrate; A semiconductor layer formed on an upper surface of the transparent electrode layer; And And a rear electrode layer formed on the semiconductor layer, Wherein the auxiliary electrode layer and the insulating layer are alternately formed at a predetermined interval in one direction. Board; A transparent electrode layer formed on an upper surface of the substrate; An auxiliary electrode layer formed on an upper surface of the transparent electrode layer; An insulating layer formed on the upper surface of the transparent electrode layer in a region between the auxiliary electrode layers; A semiconductor layer formed on an upper surface of the auxiliary electrode layer, an upper surface of the insulating layer, and an upper surface of the transparent electrode layer; And And a rear electrode layer formed on the semiconductor layer, Wherein the auxiliary electrode layer and the insulating layer are alternately formed at a predetermined interval in one direction. delete 3. The method according to claim 1 or 2, Wherein the insulating layer is formed at a higher height than the auxiliary electrode layer. 3. The method according to claim 1 or 2, Wherein the insulating layer has a structure in which transparent insulating materials are spaced apart at regular intervals. 3. 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. 3. 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. 8. The method of claim 7, Wherein 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 first bus line is exposed to the outside. 3. The method according to claim 1 or 2, The auxiliary electrode layer includes a plurality of first auxiliary electrode layers arranged in a first direction and a second auxiliary electrode layer arranged in a second direction while connecting the first auxiliary electrode layers while maintaining a predetermined gap therebetween Thin film solar cells. 3. 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. Forming an insulating layer on an upper surface of the substrate and in an area between the auxiliary electrode layer and the auxiliary electrode layer; Forming a transparent electrode layer on the upper surface of the auxiliary electrode layer, the upper surface of the insulating layer, and the upper surface of the substrate; Forming a semiconductor layer on an upper surface of the transparent electrode layer; And And forming a rear electrode layer on the semiconductor layer, Wherein the auxiliary electrode layer and the insulating layer are alternately formed at a predetermined interval in one direction. Forming a transparent electrode layer on an upper surface of a substrate; Forming an insulating layer on an upper surface of the transparent electrode layer in an area between the auxiliary electrode layer and the auxiliary electrode layer; Forming a semiconductor layer on the upper surface of the auxiliary electrode layer, the upper surface of the insulating layer, and the upper surface of the transparent electrode layer; And And forming a rear electrode layer on the semiconductor layer, Wherein the auxiliary electrode layer and the insulating layer are alternately formed at a predetermined interval in one direction. delete 13. The method according to claim 11 or 12, Wherein the step of forming the insulating layer comprises the step of forming an insulating layer having a height higher than that of the auxiliary electrode layer. 13. The method according to claim 11 or 12, Wherein the step of forming the insulating layer comprises a step of forming transparent insulating materials spaced apart from each other with a predetermined distance therebetween. 13. The method according to claim 11 or 12, Further comprising the step of forming a transparent conductive layer between the semiconductor layer and the rear electrode layer. 13. The method according to claim 11 or 12, Wherein the forming of the auxiliary electrode layer includes forming a first bus line connected to the auxiliary electrode layer, Wherein the step of forming the rear electrode layer includes forming a second bus line connected to the rear electrode layer. 18. The method of claim 17, Wherein the step of forming the transparent electrode layer, the step of forming the semiconductor layer, and the step of forming the rear electrode layer do not form respective layers on the first bus line. 13. The method according to claim 11 or 12, The auxiliary electrode layer may be formed by forming a plurality of first auxiliary electrode layers arranged in a first direction and a second auxiliary electrode layer connecting the first auxiliary electrode layers and arranged in a second direction while maintaining a predetermined gap therebetween Wherein the thin film solar cell comprises a plurality of thin film solar cells. 13. The method according to claim 11 or 12, 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 Wherein the thin film solar cell comprises a plurality of thin film solar cells.

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