KR101405023B1 - Thin film type Solar Cell, and Method for manufacturing the same - Google Patents

Abstract

According to the present invention, there is provided a method of manufacturing a light emitting device, comprising: sequentially laminating a front electrode layer, a photoelectric conversion portion, and a rear electrode layer on a substrate; Removing a predetermined region of the front electrode layer, the photoelectric conversion portion, and the rear electrode layer to form a first separator; Removing a predetermined region of the photoelectric conversion portion and the rear electrode layer to form an open portion constituting the contact portion and the second separation portion; And forming a metal layer electrically connecting the front electrode layer and the rear electrode layer through a contact portion in the open portion. The method of manufacturing a thin film solar cell according to claim 1, As a matter of fact,

According to the present invention, first, since the laser scribing process for forming the separator or the contact unit is performed after the laminating process of the front electrode layer, the photoelectric converter and the rear electrode layer is performed, It is unnecessary to repeatedly use the crying equipment alternately, so that the construction of the manufacturing equipment is simplified, the manufacturing process time is shortened and the productivity is improved, and second, the contact portion and the second separating portion are simultaneously subjected to the laser scribing process So that the number of laser scribing processes is reduced compared to the prior art, and the problem of substrate contamination due to residues is reduced.

Thin-film solar cell, metal layer

Description

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

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film solar cell, and more particularly, to a thin film solar cell having a plurality of unit cells connected in series.

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. 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. As the substrate becomes larger, the power loss due to the resistance of the transparent conductive material increases .

Therefore, a method has been devised in which a thin film solar cell is divided into a plurality of unit cells and a plurality of unit cells are connected in series so as to minimize the power loss due to the resistance of the 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 1G 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 20a is formed on a substrate 10 by using a transparent conductive material such as ZnO.

Next, as shown in FIG. 1B, a predetermined region of the front electrode layer 20a is removed to form the first separator 25. A plurality of front electrodes 20 spaced apart by the first separator 21 are formed.

Next, as shown in FIG. 1C, a semiconductor layer 30a is formed on the entire surface of the substrate 10 including the front electrode 20.

Next, as shown in FIG. 1D, a predetermined region of the semiconductor layer 30a is removed to form a contact portion 35. Next, as shown in FIG.

Next, as shown in FIG. 1E, a rear electrode layer 50a is formed on the entire surface of the substrate 10.

Next, as shown in FIG. 1F, a predetermined region of the rear electrode layer 50a and the semiconductor layer 30 is removed to form a second isolation portion 55. Next, as shown in FIG. A plurality of rear electrodes 50 spaced apart by the second separator 55 and connected to the front electrode 20 through the contact portion 35 are formed. In this way, the front electrode 20 and the rear electrode 50 are connected to each other through the contact portion 35, so that a plurality of unit cells are connected in series.

However, such a conventional method of manufacturing a thin film solar cell has the following problems.

First, since the conventional method repeats the process in the vacuum state and the process in the atmospheric state alternately, the manufacturing equipment becomes complicated and the manufacturing process takes a long time, resulting in a low productivity. A concrete description will be given below.

1A), a step of forming a first separator 25 (see FIG. 1B), a step of forming a semiconductor layer 30a (see FIG. The process of forming the contact portion 35 (see FIG. 1D), the process of forming the rear electrode layer 50a (see FIG. 1E), and the process of forming the second separator 55 (See FIG. 1F).

1C) forming the front electrode layer 20a (see FIG. 1A), forming the semiconductor layer 30a (see FIG. 1C), and forming the rear electrode layer 50a (See FIG. 1B) forming the first separator 25, the process of forming the contact portion 35 (see FIG. 1D), and the second separator 25 (See FIG. 1F) for forming the second electrode layer 55 is performed using a laser scribing device under atmospheric pressure. Therefore, in order to complete a thin film solar cell in the related art, the substrate 10 should be repeatedly injected into a vacuum deposition apparatus and a laser scribing apparatus alternately.

Meanwhile, in the process of putting the substrate into the vacuum deposition apparatus under atmospheric pressure, it is required to prevent the outside air from being introduced into the vacuum deposition apparatus. Generally, the substrate is not directly introduced into the vacuum deposition apparatus, The substrate is introduced into the vacuum deposition apparatus while the external air is prevented from flowing into the vacuum deposition apparatus through the load chamber. Therefore, when the substrate 10 is repeatedly and repeatedly injected into the vacuum vapor deposition apparatus and the laser scribing apparatus as in the related art, the equipment configuration becomes complicated due to the load lock chamber and the like, There is a problem that the process time is long.

Second, since the conventional laser scribing process is performed three times to form the first separator 25, the contact portion 35, and the second separator 55, There is a concern that the residues generated during the ice process remain on the substrate to contaminate the substrate. If a cleaning process is added to prevent contamination of the substrate, the process becomes complicated and the productivity is lowered.

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

The present invention provides a thin film solar cell and a method of manufacturing the same which can reduce the number of times of repeatedly injecting a substrate into a vacuum vapor deposition apparatus and a laser scribing apparatus alternately to simplify the manufacturing equipment construction and shorten the manufacturing process time .

Another object of the present invention is to provide a thin film solar cell capable of reducing the contamination of the substrate caused by the laser scribing process by reducing the number of laser scribing processes and a method of manufacturing the same.

In order to achieve the above-described object, the present invention provides a method of manufacturing a semiconductor device, comprising: a step of sequentially laminating a front electrode layer, a photoelectric conversion portion and a rear electrode layer on a substrate; Removing a predetermined region of the front electrode layer, the photoelectric conversion portion, and the rear electrode layer to form a first separator; Removing a predetermined region of the photoelectric conversion portion and the rear electrode layer to form an open portion constituting the contact portion and the second separation portion; And forming a metal layer electrically connecting the front electrode layer and the rear electrode layer through the contact portion in the open portion.

The photoelectric conversion portion may be formed of a semiconductor layer having a PIN structure.

The photoelectric conversion unit may include a first semiconductor layer having a PIN structure, a buffer layer formed on the first semiconductor layer, and a second semiconductor layer having a PIN structure formed on the buffer layer, wherein the first semiconductor layer is amorphous The buffer layer may be formed of a transparent conductive material, and the second semiconductor layer may be formed of a microcrystalline semiconductor material.

The method may further include forming a first insulating layer on the first separator before the step of forming the metal layer, 2 insulating layer may be further formed.

When the photoelectric conversion portion is formed of the first semiconductor layer, the buffer layer, and the second semiconductor layer, the metal layer and the buffer layer are formed on one side of the contact portion in the open portion, The third insulating layer can be formed.

The metal layer may be formed to connect the rear electrode layers spaced apart by the first separator.

The contact portion and the second separating portion are configured to be in contact with each other, and the contact portion may be formed between the first separating portion and the second separating portion.

Further comprising the step of forming a transparent conductive layer between the photoelectric conversion portion and the rear electrode layer and removing a predetermined region of the transparent conductive layer at the time of forming the first separation portion and the open portion.

The present invention also provides a plasma display panel comprising: a front electrode formed on a substrate by a first separator; A photoelectric conversion unit and a rear electrode sequentially formed on the front electrode and having an open part constituting a contact part and a second separation part; And a metal layer electrically connecting the front electrode and the rear electrode through a contact portion in the open portion.

The photoelectric conversion portion may be formed of a semiconductor layer having a PIN structure.

The photoelectric conversion unit may include a first semiconductor layer having a PIN structure, a buffer layer formed on the first semiconductor layer, and a second semiconductor layer having a PIN structure formed on the buffer layer. The first semiconductor layer may include an amorphous semiconductor The buffer layer is made of a transparent conductive material, and the second semiconductor layer is made of a microcrystalline semiconductor material.

A first insulating layer may be formed in the first separator, and a second insulating layer may be formed in the second separator in the open.

When the photoelectric conversion portion includes the first semiconductor layer, the buffer layer, and the second semiconductor layer, a third insulating layer may be formed on one side of the contact portion in the open portion, more specifically, between the metal layer and the buffer layer .

The metal layer may connect the rear electrodes separated by the first separator.

The contact portion and the second separating portion may be configured to be in contact with each other, and the contact portion may be formed between the first separating portion and the second separating portion.

A transparent conductive layer having the same pattern as that of the rear electrode may be additionally formed between the photoelectric conversion portion and the rear electrode.

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

First, since the present invention performs a laser scribing process for forming a separating unit or a contact unit after performing the laminating process of the front electrode layer, the photoelectric conversion unit, and the rear electrode layer, the conventional vacuum deposition equipment and laser scribing Since it is not necessary to repeatedly use the equipment alternately, the manufacturing equipment configuration is simplified, the manufacturing process time is shortened, and the productivity is improved.

Second, since the contact portion and the second separation portion are simultaneously formed by using the laser scribing process, the number of laser scribing processes is reduced compared to the prior art, and the problem of substrate contamination due to residues is reduced.

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

<Thin Film Solar Cell Manufacturing Method>

2A to 2D are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to an embodiment of the present invention.

2A, a front electrode layer 200a, a photoelectric conversion portion 300a, a transparent conductive layer 400a, and a rear electrode layer 500a are sequentially stacked on a substrate 100. As shown in FIG.

As the substrate 100, glass or transparent plastic may be used.

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

Since the front electrode layer 200a is a surface on which sunlight is incident, it is important that the incident sunlight can be absorbed into the solar cell as much as possible. For this purpose, a texturing process is applied to the front electrode layer 200a Can be performed. 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 the texture process is performed on the front electrode layer 200a, the ratio of the incident sunlight to the outside of the solar cell is reduced. In addition, 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 photoelectric conversion portion 300a may be formed of a silicon-based semiconductor material by using a plasma CVD method or the like and may have a PIN structure in which a P-type semiconductor layer, an I-type semiconductor layer, and an N-type semiconductor layer are stacked in order . When the photoelectric conversion portion 300a is formed as a PIN structure, the I-type semiconductor layer is depleted by the P-type semiconductor layer and the N-type semiconductor layer, and an electric field is generated therein. Holes and electrons generated by the electric field are drifted by the electric field to be collected in the P-type semiconductor layer and the N-type semiconductor layer, respectively. On the other hand, when the photoelectric conversion portion 300a is formed into a PIN structure, it is preferable to form the P-type semiconductor layer first and then form the I-type semiconductor layer and the N-type semiconductor layer in order, In general, the drift mobility of holes is low due to drift mobility of electrons, so that the P-type semiconductor layer is formed close to the light receiving surface in order to maximize collection efficiency by incident light.

The transparent conductive layer 400a may be formed of a transparent conductive material such as ZnO, ZnO: B, ZnO: Al, or Ag by sputtering or MOCVD (Metal Organic Chemical Vapor Deposition). Although the transparent conductive layer 400a may be omitted, it is preferable to form the transparent conductive layer 400a in order to improve the efficiency of the solar cell. That is, when the transparent conductive layer 400a is formed, the solar light transmitted through the photoelectric conversion portion 300a passes through the transparent conductive layer 400a and diffuses at various angles through scattering, And the ratio of light re-incident on the photoelectric conversion portion 300a can be increased.

The rear electrode layer 500a may be formed of a metal such as Ag, Al, Ag + Mo, Ag + Ni, or Ag + Cu by sputtering or the like, You may.

2B, the first separator 250 and the open part 450 are formed to form the front electrode 200, the photoelectric conversion part 300, the transparent conductive layer 400, and the rear electrode 500 ).

The first separator 250 separates the front electrodes 200 at predetermined intervals to separate the thin-film solar cells into unit cells. The first separator 250 includes the front electrode layer 200a, The photoelectric conversion portion 300a, the transparent conductive layer 400a, and the rear electrode layer 500a.

The open portion 450 constitutes a contact portion 350 and a second separator 550. The open portion 450 includes the photoelectric conversion portion 300a, the transparent conductive layer 400a, and the rear electrode layer 500a ) Is removed.

The contact unit 350 serves as a connection path for electrically connecting the front electrode 200 and the rear electrode 500 to connect the unit cells of the thin film solar cell in series, The unit 550 separates the thin film solar cell into a single wafer cell by spacing the rear electrode 500 at a predetermined interval.

The contact unit 350 and the second separator 550 are configured to be in contact with each other and the contact unit 350 is positioned between the first separator 250 and the second separator 550.

The first separator 250 and the open part 450 can be formed using a laser scribing process, and no special process order is required between them. That is, any one of the first separator 250 and the open portion 450 may be formed first, and then the remainder may be formed, and the first separator 250 may be formed by changing the structure of the laser scriber, And the open portion 450 can be formed at the same time, it is advantageous in shortening the process time.

Next, as shown in FIG. 2C, a first insulating layer 600 is formed on the first separator 250.

The first insulating layer 600 is formed to prevent the front electrodes 200 separated into unit cells from being electrically connected to each other in a process described later. A metal layer 700 is formed in order to electrically connect the front electrode 200 and the rear electrode 500 through the contact portion 350 in the open portion 450 At this time, when the metal layer 700 penetrates into the first separator 250, the front electrodes 200 separated by the unit cell are electrically connected by the metal layer 700, resulting in a short circuit.

In order to prevent the front electrodes 200 separated by the unit cells from being electrically connected by the metal layer 700, a first insulating layer 600 is formed on the first separator 250 before the metal layer 700 is formed . Since the first insulating layer 600 prevents the front electrodes 200 separated into unit cells from being electrically connected to each other, the first insulating layer 600 may be formed on the entire inner surface of the first separator 250, The first insulating layer 600 may be formed at a height equal to or higher than the height of the front electrode 200 in the first separator 250. The first insulating layer 600 may extend not only to the entire interior of the first separator 250 but also to the upper surface of the rear electrode 500.

2D, a metal layer 700 is formed to electrically connect the front electrode 200 and the rear electrode 500 through the contact portion 350 in the open portion 450. As shown in FIG.

The metal layer 700 electrically connects the front electrode 200 and the rear electrode 500 to connect the unit cells of the thin-film solar cell in series.

The metal layer 700 is formed only on the contact part 350 in the open part 450 and not on the second part 550 in the open part 450. If the metal layer 700 is formed in the second separator 550 in the open portion 450, the rear electrode 500 to be separated into unit cells is connected by the metal layer 700, .

Meanwhile, although the first separator 250 separates the front electrode 200 into unit cells, the rear electrode 500 is also separated from the first separator 250 by the first separator 250, 1 rear electrode 500 separated by the separator 250 are connected to each other through the metal layer 700 so that the entire rear electrode 500 can be electrically connected in one unit cell.

3A to 3D are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another embodiment of the present invention. This is because the second insulating layer 650 is added to the second separator 550 in the open portion 450 Type solar cell according to the above-described Figs. Therefore, the same reference numerals are assigned to the same components, and a detailed description thereof will be omitted.

3A, a front electrode layer 200a, a photoelectric conversion portion 300a, a transparent conductive layer 400a, and a rear electrode layer 500a are stacked in this order on a substrate 100. As shown in FIG.

3B, the first separator 250 and the open part 450 constituting the contact part 350 and the second separator 550 are formed to form the front electrode 200, The conversion portion 300, the transparent conductive layer 400, and the rear electrode 500 are completed.

3C, a first insulating layer 600 is formed on the first separator 250 and a second insulating layer 650 is formed on the second separator 550 in the open portion 450. [ ).

The first insulating layer 600 is formed to prevent the front electrodes 200 separated into unit cells from being electrically connected to each other in a process of forming a metal layer 700 to be described later, The second insulating layer 650 is formed to prevent the rear electrodes 500 separated into unit cells from being electrically connected to each other in a process of forming a metal layer 700 to be described later.

The metal layer 700 is formed in order to electrically connect the front electrode 200 and the rear electrode 500 through the contact portion 350 in the open portion 450. In this case, 700 penetrate into the second separator 550, the rear electrodes 500 separated into the unit cells are electrically connected by the metal layer 700, resulting in a short circuit. In order to prevent the rear electrodes 500 separated by the unit cells from being electrically connected by the metal layer 700, a second insulating layer 650 is formed on the second separator 550 before the metal layer 700 is formed .

The second insulating layer 650 may extend not only to the entire interior of the second separator 550 but also to the upper surface of the rear electrode 500.

3D, a metal layer 700 electrically connecting the front electrode 200 and the rear electrode 500 is formed through the contact portion 350 in the open portion 450, .

4A to 4D are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another embodiment of the present invention, which relates to a manufacturing process of a thin film solar cell having a tandem structure. The same reference numerals are assigned to the same components as those of the above-described embodiment, and a detailed description of the same components will be omitted.

4A, a front electrode layer 200a, a photoelectric conversion portion 300a, a transparent conductive layer 400a and a rear electrode layer 500a are stacked in this order on a substrate 100. As shown in FIG.

The step of laminating the photoelectric conversion portions 300a includes laminating the first semiconductor layer 310a, laminating the buffer layer 320a on the first semiconductor layer 310a, and laminating the buffer layer 320a on the buffer layer 320a. And the second semiconductor layer 330a.

The first semiconductor layer 310a may be formed of an amorphous semiconductor material having a PIN structure, and the second semiconductor layer 330a may be formed of a microcrystalline semiconductor material.

Since the amorphous semiconductor material absorbs light having a short wavelength and the microcrystalline semiconductor material has a characteristic of absorbing light having a long wavelength, the amorphous semiconductor material and the microcrystalline semiconductor material are combined to form the photoelectric conversion portion 300a The light absorption efficiency can be enhanced. In addition, there is a problem that the amorphous semiconductor material accelerates the deterioration phenomenon when exposed to light for a long time. When the amorphous semiconductor material is formed on the side where the sunlight is incident and the microcrystalline semiconductor material is formed on the opposite side, Can be reduced. Accordingly, the first semiconductor layer 310a, which is closer to the side where the sunlight is incident, is formed of an amorphous semiconductor material and the second semiconductor layer 330a farther from the side where the sunlight is incident can be formed of a microcrystalline semiconductor material . However, the present invention is not limited thereto, and the second semiconductor layer 330a may be variously modified, such as an amorphous semiconductor material, an amorphous silicon / germanium material, or the like.

The buffer layer 320a is formed between the first semiconductor layer 310a and the second semiconductor layer 330a so that the first semiconductor layer 310a and the second semiconductor layer 330a are electrically connected to each other through a tunnel junction, And to facilitate the movement of electrons. That is, in order for the electrons generated in the first semiconductor layer 310a to move to the second semiconductor layer 330a, a tunneling process is performed between the first semiconductor layer 310a and the second semiconductor layer 330a For this purpose, the buffer layer 320a is formed. The buffer layer 320a is formed using a transparent conductive material such as ZnO.

4B, the first separator 250 and the open portion 450 are formed to form the front electrode 200, the photoelectric conversion portion 300, the transparent conductive layer 400, and the rear electrode 500 ).

The first separator 250 is formed by removing predetermined regions of the front electrode layer 200a, the photoelectric conversion portion 300a, the transparent conductive layer 400a, and the rear electrode layer 500a.

The open portion 450 constitutes a contact portion 350 and a second separator 550. The open portion 450 includes the photoelectric conversion portion 300a, the transparent conductive layer 400a, and the rear electrode layer 500a ) Is removed.

4C, a first insulating layer 600 is formed on the first separator 250 and a third insulating layer 680 is formed on one side of the contact portion 350. Referring to FIG.

The first insulating layer 600 is formed to prevent the front electrodes 200 separated into unit cells from being electrically connected to each other by the metal layer 700 in the process of FIG. .

The third insulating layer 680 serves to prevent short-circuiting between the metal layer 700 and the buffer layer 320 in the process of FIG. 4D, which will be described later. 4D, when the metal layer 700 is electrically connected to the rear electrode 500 adjacent to the front electrode 200, the metal layer 700 may be formed of a transparent conductive material in the photoelectric conversion portion 300 A third insulating layer 680 is formed in order to prevent the metal layer 700 from contacting the buffer layer 320. The third insulating layer 680 may be formed of a material having a high dielectric constant.

Thus, the third insulating layer 680 is formed to contact the buffer layer 320 on one side of the contact portion 350, that is, in the contact portion 350, so that after the process of FIG. 4D, A third insulating layer 680 is formed between the first insulating layer 700 and the buffer layer 320.

4D, a metal layer 700 is formed to electrically connect the front electrode 200 and the rear electrode 500 through the contact portion 350 in the open portion 450. Referring to FIG.

FIGS. 5A to 5D are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another embodiment of the present invention, and also a manufacturing process of a thin film solar cell having a tandem structure. FIG. The same reference numerals are assigned to the same components as those of the above-described embodiment, and a detailed description of the same components will be omitted.

5A, a front electrode layer 200a, a photoelectric conversion portion 300a, a transparent conductive layer 400a, and a rear electrode layer 500a are sequentially stacked on a substrate 100. As shown in FIG.

5B, the first separator 250 and the open part 450 constituting the contact part 350 and the second separator 550 are formed to form the front electrode 200, the photoelectric The conversion portion 300, the transparent conductive layer 400, and the rear electrode 500 are completed.

5C, a first insulating layer 600 is formed on the first separator 250 and a second insulating layer 600 is formed on the second separator 550 in the open portion 450. In this case, And a third insulating layer 680 is formed on one side of the contact portion 350 in the open portion 450.

5D, a metal layer 700 electrically connecting the front electrode 200 and the rear electrode 500 is formed through the contact part 350 in the open part 450, .

<Thin-film solar cell>

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

6, the thin film solar cell according to an embodiment of the present invention includes a substrate 100, a front electrode 200, a photoelectric conversion unit 300, a transparent conductive layer 400, a rear electrode 500, 1 insulating layer 600 and a metal layer 700.

The front electrode 200 is formed on the substrate 100 and is spaced apart by the first separator 250. The front electrode 200 is ZnO, ZnO: B, ZnO: Al, SnO _2, SnO _2: F, the surface may be made of a transparent conductive material, in order to increase the sunlight absorption, such as ITO (Indium Tin Oxide) Can be formed in a concavo-convex structure.

The photoelectric conversion unit 300 is formed on the front electrode 200 and includes a first separator 250 and an open unit 450. The open portion 450 constitutes a contact portion 350 and a second separation portion 550. The contact portion 350 and the second separation portion 550 are configured to be in contact with each other and the contact portion 350 Is formed between the first separator 250 and the second separator 550. The photoelectric conversion portion 300 may be formed of a silicon-based semiconductor material having a PIN structure in which a P-type semiconductor layer, an I-type semiconductor layer, and an N-type semiconductive layer are sequentially stacked.

The transparent conductive layer 400 is formed on the photoelectric conversion portion 300 and includes a first separator 250 and an open portion 450. The transparent conductive layer 400 may be formed of a transparent conductive material such as ZnO, ZnO: B, ZnO: Al, or Ag, and may be omitted depending on circumstances.

The rear electrode 500 is formed on the transparent conductive layer 400 and includes a first separator 250 and an open portion 450. In particular, 550). One rear electrode 500 in the unit cell is separated by the first separator 250, but is electrically connected by the metal layer 700. The rear electrode 500 may be formed of a metal such as Ag, Al, Ag + Mo, Ag + Ni, or Ag + Cu.

The first insulating layer 600 is formed on the first separator 250 to prevent electrically connected front electrodes 200 from being formed. The first insulating layer 600 may have a height equal to or greater than that of the front electrode 200 in the first separator 250 and may extend to the top surface of the rear electrode 500 .

The metal layer 700 electrically connects the front electrode 200 and the rear electrode 500 through the contact part 350. In addition, the metal layer 700 connects the rear electrodes 500 separated by the first separator 250 so that the entire rear electrodes 500 can be electrically connected in one unit cell.

7 is a schematic cross-sectional view of a thin film solar cell according to another embodiment of the present invention, except that a second insulating layer 650 is additionally formed in the second separator 550 in the open portion 450 And is the same as the thin film type solar cell according to Fig. Therefore, the same reference numerals are assigned to the same components, and a detailed description thereof will be omitted.

FIG. 8 is a schematic cross-sectional view of a thin film solar cell according to another embodiment of the present invention, which relates to a manufacturing process of a thin film solar cell having a tandem structure. A detailed description of the same configuration as that of the above-described embodiment will be omitted.

8, the thin film solar cell according to another embodiment of the present invention includes a substrate 100, a front electrode 200, a photoelectric conversion unit 300, a transparent conductive layer 400, a rear electrode 500, A first insulating layer 600, a third insulating layer 680, and a metal layer 700.

The photoelectric conversion unit 300 includes a first semiconductor layer 310, a buffer layer 320 formed on the first semiconductor layer 310, and a second semiconductor layer 330 formed on the buffer layer 320 . The buffer layer 320 is made of a transparent conductive material such as ZnO, and the second semiconductor layer 330 is made of a microcrystalline semiconductor material. The first semiconductor layer 310 is made of amorphous semiconductor material having a PIN structure. . However, the present invention is not limited thereto. The second semiconductor layer 330 may be formed of amorphous semiconductor material, amorphous silicon / germanium material, or the like.

The third insulating layer 380 is formed on one side of the contact portion 350 in the open portion 450 and is formed between the metal layer 700 and the buffer layer 320.

FIG. 9 is a schematic cross-sectional view of a thin film solar cell according to another embodiment of the present invention, which is related to a manufacturing process of a thin film solar cell having a tandem structure and includes a second separator 550 8, except that a second insulating layer 650 is additionally formed on the first insulating layer 650. The second insulating layer 650 is formed on the second insulating layer 650, as shown in FIG.

The thin film solar cell of the present invention according to the above-described Figs. 6 to 9 is manufactured by the method according to Figs. 2A to 2D, 3A to 3D, 4A to 4D and 5A to 5D, But it is not necessarily limited thereto.

1A to 1F are cross-sectional views illustrating a manufacturing process of a conventional thin film solar cell.

2A to 2D are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to an embodiment of the present invention.

3A to 3D are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another embodiment of the present invention.

4A to 4D are cross-sectional views illustrating a manufacturing process of a thin film solar cell according to another embodiment of the present invention.

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

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

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

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

9 is a cross-sectional view 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: front electrode

250: first separator 300: photoelectric converter

310: first semiconductor layer 320: buffer layer

330: second semiconductor layer 350:

400: transparency front layer 450: open section

500: rear electrode 550: second separator

600: first insulating layer 650: second insulating layer

680 third insulating layer 700 metal layer

Claims (24)

A step of sequentially laminating a front electrode layer, a photoelectric conversion portion and a rear electrode layer on a substrate; Removing a predetermined region of the front electrode layer, the photoelectric conversion portion, and the rear electrode layer to form a first separator; Removing a predetermined region of the photoelectric conversion portion and the rear electrode layer to form an open portion constituting the contact portion and the second separation portion; And And forming a metal layer electrically connecting the front electrode layer and the rear electrode layer through a contact portion in the open portion. delete delete delete The method according to claim 1, Further comprising forming a first insulating layer on the first separator before the step of forming the metal layer. The method according to claim 1, Further comprising the step of forming a second insulating layer in the second separating portion in the opening portion before the step of forming the metal layer. The method according to claim 1, Further comprising the step of forming a third insulating layer on one side of the contact portion in the open portion before the step of forming the metal layer. delete The method according to claim 1, Wherein the metal layer is formed to connect between the rear electrode layers separated by the first separator. The method according to claim 1, Wherein the contact portion and the second separation portion are configured to be in contact with each other, and the contact portion is formed between the first separation portion and the second separation portion. delete A front electrode spaced apart from the substrate by a first separator; A photoelectric conversion unit and a rear electrode sequentially formed on the front electrode and having an open part constituting a contact part and a second separation part; And And a metal layer electrically connecting the front electrode and the rear electrode through a contact portion in the open portion. delete delete delete 13. The method of claim 12, And a first insulating layer is formed on the first separator. 13. The method of claim 12, And a second insulation layer is formed in the second isolation portion in the open portion. 13. The method of claim 12, And a third insulating layer is formed on one side of the contact portion in the open portion. delete 13. The method of claim 12, And the metal layer connects between the rear electrodes separated by the first separator. 13. The method of claim 12, Wherein the contact portion and the second separation portion are configured to be in contact with each other, and the contact portion is formed between the first separation portion and the second separation portion. delete A step of sequentially laminating a front electrode layer, a photoelectric conversion portion and a rear electrode layer on a substrate; Removing a predetermined region of the front electrode layer, the photoelectric conversion portion, and the rear electrode layer to form a first separator; Removing a predetermined region of the photoelectric conversion portion and the rear electrode layer to form an open portion constituting the contact portion and the second separation portion; And And forming a metal layer electrically connecting the front electrode layer and the rear electrode layer through the contact portion in the open portion, Wherein the step of forming the first separator and the step of forming the open part are performed at the same time. 24. The method of claim 1 or 23, Wherein the step of forming the first separator comprises performing scribing in the order of the rear electrode layer, the photoelectric conversion portion, and the front electrode layer, Wherein the step of forming the open portion performs scribing in the order of the rear electrode layer and the photoelectric conversion portion.

Images