KR20140052390A - Thin film solar cell and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a thin film solar cell and a manufacturing method thereof.
A thin film solar cell according to the present invention includes: a substrate; A first electrode disposed on the substrate; A photoelectric conversion unit disposed on the first electrode; And a second electrode disposed on the photoelectric conversion portion, wherein a plurality of oxide particles are disposed at an interface between the first electrode and the substrate.
A method of manufacturing a thin film solar cell according to the present invention includes the steps of dispersing and distributing a plurality of oxide particles on a substrate; Forming a first electrode on a substrate on which a plurality of oxide particles are distributed; Forming a photoelectric conversion portion on the first electrode; And forming a second electrode on the photoelectric conversion portion.

Description

[0001] THIN FILM SOLAR CELL AND MANUFACTURING METHOD THEREOF [0002]

The present invention relates to a thin film solar cell and a manufacturing method thereof.

Recently, as energy resources such as oil and coal are expected to be depleted, interest in alternative energy to replace them is increasing, and solar cells that produce electric energy from solar energy are attracting attention.

Typical solar cells have a semiconductor portion that forms a p-n junction by different conductive types, such as p-type and n-type, and electrodes connected to semiconductor portions of different conductivity types, respectively.

When light is incident on the solar cell, a plurality of electron-hole pairs are generated in the semiconductor, and the generated electron-hole pairs are separated into electrons and holes. The electrons are moved toward the n-type semiconductor portion, . The transferred electrons and holes are collected by the different electrodes connected to the p-type semiconductor portion and the n-type semiconductor portion, respectively, and the electrodes are connected by a wire to obtain electric power.

An object of the present invention is to provide a thin film solar cell with improved efficiency.

A thin film solar cell according to the present invention includes: a substrate; A first electrode disposed on the substrate; A photoelectric conversion unit disposed on the first electrode; And a second electrode disposed on the photoelectric conversion portion, wherein a plurality of oxide particles are disposed at an interface between the first electrode and the substrate.

Here, the refractive index of the plurality of oxide particles may have a value between the refractive index of the substrate and the refractive index of the first electrode. In one example, the refractive index of the plurality of oxide particles may have a value between 1.5 and 2.0.

Here, the sizes of the plurality of oxide particles may be uneven. That is, the plurality of oxide particles may include a first particle having a size larger than the first size and a second particle having a size smaller than the first size.

Here, the size of the plurality of oxide particles may be between 5 nm and 500 nm.

In addition, the plurality of oxide particles may include a transparent material. In one example, the plurality of oxide particles may comprise at least one of SiO ₂ , TiO ₂ , SiO x N y and Al ₂ O ₃ .

Also, the surface of the first electrode facing the substrate may include a plurality of irregularities, and the thickness of the first electrode may be between 500 nm and 1.5 占 퐉.

In addition, the first electrode may include a transparent conductive material. Specifically, the first electrode may include at least one of a ZnO-based material and a SnO-based material. For example, the first electrode may include zinc oxide (ZnOx) , Tin oxide (SnOx), indium oxide (InOx), zinc boron oxide (ZnO: B, BZO) and aluminum zinc oxide (ZnO: Al, AZO).

Here, the photoelectric conversion unit may include at least one photoelectric conversion layer including a pinned semiconductor layer.

A method of manufacturing a thin film solar cell according to the present invention includes the steps of dispersing and distributing a plurality of oxide particles on a substrate; Forming a first electrode on a substrate on which a plurality of oxide particles are distributed; Forming a photoelectric conversion portion on the first electrode; And forming a second electrode on the photoelectric conversion portion.

Here, dispersing and distributing the plurality of oxide particles includes the steps of spraying a solution containing a plurality of oxide particles onto the substrate; And drying the solution containing a plurality of oxide particles sprayed on the substrate.

In addition, the first electrode may be formed by at least one of chemical vapor deposition (CVD, PECVD) and sputtering methods.

At this time, the etching process for the first electrode may be omitted.

The thin film solar cell according to the present invention has a structure in which a plurality of interfacial oxide particles are formed between the first electrode and the substrate and the surface of the first electrode is formed into a plurality of concavo-convex shapes by the oxide particles, Can be improved.

1 is a view for explaining an example of a thin film solar cell according to the present invention.
FIG. 2 is an enlarged view of a portion A in FIG. 1 in order to explain a plurality of oxide particles in a thin film solar cell according to the present invention in more detail.
3 is a view for explaining an example of a double junction solar cell or pinpin structure according to the present invention.
4 is a view for explaining an example of a triple junction solar cell or pinpinpin structure according to the present invention.
5 to 8 are views for explaining an example of a method of manufacturing a thin film solar cell according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

In the drawings, the thickness is enlarged to clearly represent the layers and regions. When a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case directly above another portion but also the case where there is another portion in between. Conversely, when a part is "directly over" another part, it means that there is no other part in the middle. Also, when a part is formed as "whole" on the other part, it means not only that it is formed on the entire surface (or the front surface) of the other part but also not on the edge part.

1 is a view for explaining an example of a thin film solar cell according to the present invention.

1, an example of a thin film solar cell according to the present invention includes a substrate 100, a plurality of oxide particles 110P, a first electrode 110, a photoelectric conversion unit PV, a rear reflective layer 130, And a second electrode (140).

Here, although the back reflection layer 130 can be omitted, since the efficiency of the thin film solar cell is improved, the description will be made as shown in FIG.

The substrate 100 may be made of a substantially transparent non-conductive material, such as glass or plastic, to allow the incident light Light to reach the photoelectric conversion part PV more effectively.

The first electrode 110 is disposed on the substrate 100 and includes at least one transparent conductive oxide (TCO) material selected from a substantially transparent conductive material, for example, a ZnO-based material and a SnO-based material, for increasing the transmittance of incident light. ≪ / RTI >

More specifically, the first electrode 110 may include at least one of indium tin oxide (ITO), zinc oxide (ZnOx), tin oxide (SnOx), indium oxide (InOx), boron zinc oxide (ZnO: B, BZO) And a zinc oxide (ZnO: Al, AZO).

The first electrode 110 may be electrically connected to the photoelectric conversion unit PV. Accordingly, the first electrode 110 can collect and output one of the carriers generated by the incident light, for example, holes.

In addition, a plurality of irregularities may be formed on the surface of the first electrode 110 that contacts the photoelectric conversion unit PV. As described above, the plurality of irregularities formed on the first electrode 110 reduce reflection of incident light, increase the scattering rate of the light transmitted through the first electrode 110, and increase the amount of light absorbed by the photoelectric conversion unit PV The efficiency of the solar cell can be further improved.

Unlike the conventional method of etching the surface on which the photoelectric conversion unit PV is deposited by the first electrode 110 to form the surface irregularities of the first electrode 110, A plurality of oxide particles 110P are dispersed and distributed on the interface between the first electrode 110 and the substrate 100 to form concave and convex portions on one surface of the first electrode 110, for example, a surface on which the photoelectric conversion portion PV is deposited .

Such a plurality of oxide particles 110P will be described in more detail in Fig.

The photoelectric conversion unit PV is formed on the first electrode 110 and functions to convert light incident from the outside through the incident surface of the substrate 100 into electricity.

Such a photoelectric conversion portion PV includes a pin structure, that is, a p-type semiconductor layer p, an intrinsic (i-type) semiconductor layer i, and an n-type semiconductor layer n from the incident surface of the substrate 100 can do.

In FIG. 1, the photoelectric conversion portion PV is a single photoelectric conversion layer forming a pin semiconductor layer. However, the photoelectric conversion layer forming the pin semiconductor layer in the photoelectric conversion portion PV Two or three layers.

For a double junction structure having two photoelectric conversion layers forming a p-i-n semiconductor layer, a triple junction structure having three photoelectric conversion layers for forming a p-i-n semiconductor layer will be described in more detail with reference to FIG.

1, the structure of the photoelectric conversion unit PV has a p-i-n structure from the incident plane. However, it is also possible that the structure of the photoelectric conversion unit PV has an n-i-p structure from the incident plane. However, for convenience of description, the structure of the photoelectric conversion portion PV is a p-i-n structure from the incident side will be described below as an example.

Here, the p-type semiconductor layer p is formed by doping a source gas containing silicon (Si) with a first type impurity such as boron (B, Baron), gallium (Ga), indium It can be formed by using a gas containing an impurity.

The n-type semiconductor layer n may be formed by doping a source gas containing silicon with impurities of a second type opposite to the first type such as phosphorus (P), arsenic (As), antimony (Sb) It can be formed using a gas containing an impurity.

The intrinsic (i) semiconductor layer (i) is disposed between the p-type semiconductor layer (p) and the n-type semiconductor layer, and can reduce the recombination rate of carriers and absorb light. The intrinsic semiconductor layer (i) absorbs incident light and can generate carriers such as electrons and holes.

Thus, the p-type semiconductor layer (p) and the n-type semiconductor layer (n) form a p-n junction with the intrinsic semiconductor layer (i) sandwiched therebetween.

The intrinsic semiconductor layer i may be amorphous silicon containing carbon (C), or crystalline silicon containing carbon (C), or may be composed of microcrystalline silicon (mc-SiC) containing carbon (C) It is possible.

The photoelectric conversion part PV including the p-i-n semiconductor layer may be formed by chemical vapor deposition (CVD) such as plasma enhanced chemical vapor deposition (PECVD).

The rear reflective layer 130 is disposed on the photoelectric conversion unit PV and functions to reflect the light not absorbed in the photoelectric conversion unit PV to the photoelectric conversion unit PV.

The rear reflective layer 130 may include a transparent transparent oxide. For example, the rear reflective layer 130 may be formed of a transparent conductive oxide (TCO) in the same manner as the first electrode 110.

The second electrode 140 is disposed on the rear reflective layer 130 and may include a metal material having excellent electrical conductivity in order to increase the efficiency of recovery of electric power generated in the photoelectric conversion unit PV.

In addition, the second electrode 140 is electrically connected to the photoelectric conversion unit PV, and can collect and output one of the carriers generated by the incident light, for example, electrons.

The second electrode 140 may include at least one of silver (Ag) and aluminum (Al) having good electrical conductivity. The second electrode 140 may be a single layer or a multilayer.

In this case, the light is incident on the opposite side of the substrate 100, that is, the second electrode 140. In this case, the second electrode 140, Transmissive conductive material, and the first electrode 110 may be formed of a metal material.

In this structure, when light is incident on the p-type semiconductor layer (p), the p-type semiconductor layer (p) and the n-type semiconductor layer (n) having a relatively high doping concentration inside the intrinsic semiconductor layer a depletion is formed, whereby an electric field can be formed. Due to the photovoltaic effect, the electrons and holes generated in the intrinsic semiconductor layer i, which is the light absorbing layer, are separated by the contact potential difference and moved in different directions. For example, the holes may move toward the front electrode 110 through the p-type semiconductor layer p and electrons may move toward the rear electrode 140 through the n-type semiconductor layer n. Power can be produced in this way.

In the case where the plurality of oxide particles 110P are dispersed in the interface between the first electrode 110 and the substrate 100 as in the present invention, the scattering effect of the light incident on the first electrode 110 And the haze ratio (scattered light / transmitted light) can be increased, thereby further improving the efficiency of the solar cell.

In addition, in order to increase the light scattering effect in the state where the first electrode 110 is deposited on the substrate 100, a structure of the first electrode 110, on which the photoelectric conversion unit PV is deposited, A plurality of oxide particles 110P are formed on the substrate 100 instead of the etching process to form concave and convex portions on the surface on which the photoelectric conversion portion PV is to be deposited in the first electrode 110, And the manufacturing cost can be further reduced.

Hereinafter, the structure of the thin film solar cell of the present invention will be described first, and then the manufacturing process will be described.

FIG. 2 is an enlarged view of a portion A in FIG. 1 in order to explain a plurality of oxide particles in a thin film solar cell according to the present invention in more detail.

2, a plurality of oxide particles 110P according to the present invention are dispersed and distributed on the interface between the first electrode 110 and the substrate 100, and the first electrode 110 includes a plurality of oxide particles 110P, (110P) may be deposited on the distributed substrate (100).

The first electrode 110 has a plurality of projections and depressions formed on a surface 110S1 of the substrate 100 that directly contacts the substrate 100 and a plurality of oxide particles 110P, A plurality of concavities and convexities are also formed on the surface 110S2.

Accordingly, the first electrode 110 is formed with a plurality of projections and depressions on the surface 110S1 of the substrate 100 side and the surface 110S2 of the photoelectric conversion portion PV side, respectively.

Accordingly, the light incident through the substrate 100 is primarily scattered (S1) and transmitted through the irregularities formed on the surface 110S1 of the first electrode 110 on the substrate 100 side, and is scattered as described above The transmitted light can be scattered (S2) on the surface 110S2 of the photoelectric conversion portion (PV) side of the first electrode 110.

Accordingly, when light incident from the outside passes through the first electrode 110, the amount of scattered light can be further increased, so that the light in the long wavelength band is absorbed more easily in the photoelectric conversion unit PV can do. Therefore, the photoelectric conversion efficiency of the solar cell can be further increased.

The concave and convex portions are formed only on the surface of the photoelectric conversion portion PV side without forming the concave and convex on the surface 110S1 of the first electrode 110 disposed on the substrate 100 in the conventional case , The present invention is characterized in that not only the surface 110S1 of the first electrode 110 on the side of the substrate 100 but also the surface 110S2 of the photoelectric conversion portion PV side are formed with irregularities so that the egg- It can be further increased as compared with the prior art.

The refractive indices of the plurality of oxide particles 110P dispersed and distributed on the interface between the first electrode 110 and the substrate 100 may be adjusted by changing the refractive index of the substrate 100 And the refractive index of the first electrode 110 may be set to have a value between the refractive index of the first electrode 110 and the refractive index of the first electrode 110.

Therefore, for example, when the refractive index of the substrate 100 is 1.5 and the refractive index of the photoelectric conversion portion PV is 2.0, the refractive index of the plurality of oxide particles 110P may have a value between 1.5 and 2.0. However, when the refractive indexes of the substrate 100 and the photoelectric conversion portion PV are changed, the refractive index of the plurality of oxide particles 110P may also be changed somewhat.

The reason why the plurality of oxide particles 110P are dispersed and distributed at the interface between the first electrode 110 and the substrate 100 is that the surface of the first electrode 110 has a plurality of irregularities .

Therefore, the larger the roughness of the surface of the first electrode 110 due to the unevenness, the more the scattering rate, that is, the haze ratio, of the incident light can be further increased and the light absorption rate of the photoelectric conversion unit PV can be further increased have.

Therefore, in order to increase the roughness of the irregularities formed on the surface of the first electrode 110, the shape and size of the plurality of oxide particles 110P distributed and distributed on the first electrode 110 may be uneven .

That is, although the shape of the plurality of oxide particles 110P may be circular, in order to increase the roughness of the surface of the first electrode 110, the shape of the plurality of oxide particles 110P may be polygonal rather than circular, The shape is more effective.

In addition, the size of the plurality of oxide particles 110P may be uneven. That is, the plurality of oxide particles 110P dispersedly distributed on the first electrode 110 include the first particles 110P1 and the second particles 110P2 having a size larger or smaller than the first particles 110P1 And the first particles 110P1 and the second particles 110P2 having such various sizes can be dispersed non-uniformly on the surface of the substrate 100. [

In addition, as shown in FIG. 2, in order to further increase the surface roughness of the first electrode 110, it is more preferable that the particles having various sizes are formed to be spaced apart from each other.

Of course, some of the particles may be formed in contact with each other during the manufacturing process. However, since most particles having various sizes and shapes are dispersed and distributed on the interface between the substrate 100 and the first electrode 110, The surface roughness of the electrode 110 can be further increased.

At this time, the surface roughness of the first electrode 110 can be further increased as the intervals D110P where the plurality of oxide particles 110P are spaced apart become uniform.

In consideration of the concavities and convexities to be formed in the first electrode 110, the size of the plurality of oxide particles 110P may be dispersed nonuniformly on the surface of the substrate 100 in various sizes between 5 nm and 500 nm .

In this case, the first particle 110P1 may be a particle having a size of 300 nm to 500 nm, and the second particle 110P2 may be a particle having a particle size of 5 nm to 300 nm.

The first electrode 110 may have a thickness ranging from about 500 nm to about 1.5 μm. In this case, the surface roughness of the first electrode 110 formed by the plurality of oxide particles 110P may be maximized, In order to maintain good electrical conductivity of the first electrode 110.

The thickness of the first electrode 110 is set to be from the surface of the first electrode 110 facing the substrate 100 to the surface of the first electrode 100 facing the photoelectric conversion unit PV, Is the thickness measured in a direction perpendicular to the plane of the substrate.

When the sizes of the plurality of oxide particles 110P distributed to the thickness of the first electrode 110 are excessively small, the size of the surface irregularities of the first electrode 110 formed by the plurality of oxide particles 110P is The surface roughness of the first electrode 110 may be relatively small.

On the contrary, when the size of the plurality of oxide particles 110P distributed to the thickness of the first electrode 110 is excessively large, the first electrode 110 deposited on the substrate 100 and the plurality of oxide particles 110P, A minute crack may be generated in a part of the first electrode 110. In such a case, the electrical conductivity of the first electrode 110 may be lowered.

Therefore, in consideration of this point, the size of the plurality of oxide particles 110P may be formed in various sizes between 5 nm and 500 nm. However, the size of the plurality of oxide particles 110P may vary depending on the thickness of the first electrode 110. [

Such a plurality of oxide particles 110P may include a transparent material and may be non-conductive to minimize reflectance. In one example, the plurality of the oxide particles (110P) may include at least one material selected from the group consisting of SiO _2, TiO _2, SiOxNy, and Al ₂ O _3.

However, the plurality of oxide particles 110P is not necessarily limited to such a material, and any other transparent material may be included, and the oxide particle 110P may also include a transparent conductive material.

Up to now, one photoelectric conversion layer of the photoelectric conversion part PV has been described as an example, but a case of two or three photoelectric conversion parts PV will be described below.

3 is a view for explaining an example of a double junction solar cell or a p-i-n-p-i-n structure according to the present invention.

Hereinafter, the description of the parts overlapping with those described in detail above will be omitted.

3, in the thin film solar cell, the photoelectric conversion unit PV is connected to the first photoelectric conversion layer PV1 and the first photoelectric conversion layer PV1 disposed adjacent to the substrate 100, And a second photoelectric conversion layer (PV2) that is further away from the first photoelectric conversion layer (PV2).

As shown in Fig. 3, the thin film solar cell includes a first p-type semiconductor layer PV1-p, a first i-type semiconductor layer PV1-i, a first n-type semiconductor layer PV1-n, The second p-type semiconductor layer PV2-p, the second i-type semiconductor layer PV2-i, and the second n-type semiconductor layer PV2-n may be sequentially stacked.

The first i-type semiconductor layer PV1-i can mainly absorb light in a short wavelength band to generate electrons and holes. In addition, the second i-type semiconductor layer (PV2-i) can mainly absorb light in a long wavelength band to generate electrons and holes.

As described above, a solar cell having a double junction structure can have high efficiency because it absorbs light in a short wavelength band and a long wavelength band to generate a carrier.

In addition, the thickness of the second i-type semiconductor layer PV2-i may be thicker than the thickness of the first i-type semiconductor layer PV1-i to sufficiently absorb light in the long wavelength band.

3, the first i-type semiconductor layer PV1-i of the first photoelectric conversion layer PV1 may include amorphous silicon (a-Si), and the first i- The second i-type semiconductor layer PV2-i of the second photoelectric conversion layer PV2 may include microcrystalline silicon (mc-SiC) containing carbon.

The solar cell having the double junction structure shown in Fig. 3 absorbs light of a short wavelength band in the first i-type semiconductor layer PV1-i to exert a photoelectric effect, and the second i-type semiconductor layer PV2- When the second i-type semiconductor layer PV2-i contains microcrystalline silicon (mc-SiC) as described above, a larger amount of long wavelength band (mc-SiC) The light can be absorbed and the efficiency of the solar cell can be improved.

In the solar cell having such a double junction structure, as described with reference to FIG. 2, a plurality of oxide particles 110P dispersedly distributed on the interface between the first electrode 110 and the substrate 100 may be included.

Here, the structure of the plurality of oxide particles 110P and the effect thereof are the same as those described in Fig. 2, and therefore, the description thereof will be omitted.

4 is a view for explaining an example of a triple junction solar cell or a p-i-n-p-i-n-p-i-n structure according to the present invention.

Hereinafter, the description of the parts overlapping with those described in detail above will be omitted.

4, the thin film solar cell has a structure in which a first photoelectric conversion layer PV1, a second photoelectric conversion layer PV2, and a third photoelectric conversion layer PV3 are sequentially arranged from the incident surface of the substrate 100 .

The first photoelectric conversion layer PV1 is disposed adjacent to the substrate 100 and the second photoelectric conversion layer PV2 is farther from the substrate 100 than the first photoelectric conversion layer PV1, The third photoelectric conversion layer PV3 is spaced further from the substrate 100 than the second photoelectric conversion portion PV.

Each of the first photoelectric conversion layer PV1, the second photoelectric conversion layer PV2 and the third photoelectric conversion layer PV3 may be formed in a pin structure so that the first p-type semiconductor layer The first intrinsic semiconductor layer PV1-p, the first intrinsic semiconductor layer PV1-i, the first n-type semiconductor layer PV1-n, the second p-type semiconductor layer PV2- The second n-type semiconductor layer PV2-n, the third p-type semiconductor layer PV3-p, the third intrinsic semiconductor layer PV3-i, and the third n-type semiconductor layer PV3- .

Here, the first intrinsic semiconductor layer PV1-i, the second intrinsic semiconductor layer PV2-i, and the third intrinsic semiconductor layer PV3-i can be variously formed.

4, the first intrinsic semiconductor layer PV1-i and the second intrinsic semiconductor layer PV2-i include amorphous silicon (a-Si) material, the third intrinsic semiconductor layer PV3-i, May comprise a microcrystalline silicon (mc-Si) material.

Here, the second intrinsic semiconductor layer PV2-i may contain germanium (Ge), and the third intrinsic semiconductor layer PV3-i may contain carbon (C).

In this case, the first intrinsic semiconductor layer PV1-i has the highest energy band gap and mainly absorbs light of a short wavelength, and the second intrinsic semiconductor layer PV2-i includes the amorphous silicon (a-Si) However, the third intrinsic semiconductor layer PV3-i contains carbon (C) because it contains germanium (Ge) and has an energy band gap lower than that of the first intrinsic semiconductor layer (PV1-i) ), But it contains microcrystalline silicon (mc-Si) material, so it has the lowest energy bandgap and can mainly absorb light of a long wavelength band.

Accordingly, the triple junction solar cell effectively absorbs light of a wider wavelength band than the double junction solar cell, and thus the photoelectric conversion efficiency is further improved.

Here, the thickness of the second intrinsic semiconductor layer PV2-i may be thicker than the thickness of the first intrinsic semiconductor layer PV1-i, and the thickness of the third intrinsic semiconductor layer PV3- Lt; RTI ID = 0.0 > PV2-i. ≪ / RTI > This is to further improve the light absorptance in the long wavelength band in the third intrinsic semiconductor layer (PV3-i).

As described above, in the case of the triple junction solar cell as shown in FIG. 4, since the light of a wider band can be absorbed, the power production efficiency can be high.

In a solar cell having such a triple junction structure, as shown in FIG. 2, a plurality of oxide particles 110P dispersed and distributed on the interface between the first electrode 110 and the substrate 100 may be included.

Here, the structure of the plurality of oxide particles 110P and the effect thereof are the same as those described in Fig. 2, and therefore, the description thereof will be omitted.

Although only the structure of the thin film solar cell according to the present invention has been described so far, an example of a method of manufacturing such a thin film solar cell will be described below.

5 to 8 are views for explaining an example of a method of manufacturing a thin film solar cell according to the present invention.

The present invention comprises dispersing and distributing a plurality of oxide particles (110P) on a substrate (100).

To this end, as shown in FIG. 5, a step of spraying a solution W110P containing a plurality of oxide particles 110P onto the substrate 100 may be included.

5, the step of spraying a solution W110P containing a plurality of oxide particles 110P may include spraying a solution W110P containing a plurality of oxide particles 110P onto the substrate 100 as an example, ) ≪ / RTI >

Here, the shape, size, refractive index and material of the plurality of oxide particles 110P are the same as those described with reference to FIG. 2, and a detailed description thereof will be omitted.

Here, the solution W110P containing a plurality of oxide particles 110P may be pure water, for example, and may be used irrespective of the type in which a plurality of oxide particles 110P are not dissolved.

Next, a step of drying a solution W110P including a plurality of oxide particles 110P sprayed on the substrate 100 may be performed.

As described above, by the process of drying the solution, a plurality of oxide particles 110P contained in the solution W110P can be distributed and distributed on the surface of the substrate 100, as shown in Fig.

Then, as shown in FIG. 7, the first electrode 110 is formed on the substrate 100 on which the plurality of oxide particles 110P are distributed.

Here, the materials included in the first electrode 110 are the same as those described above with reference to FIGS.

The first electrode 110 may be formed by at least one of chemical vapor deposition (CVD), sputtering (PECVD), and sputtering.

The surface 110S1 of the first electrode 110 and the surface 110S1 on which the photoelectric conversion portion PV is to be deposited by the plurality of oxide particles 110P distributed on the substrate 100 110S2 are formed with a plurality of irregularities.

Therefore, in the solar cell according to the present invention, the first electrode 110 for forming a plurality of projections and depressions on the surface of the first electrode 110 contacting the photoelectric conversion unit PV is etched by etching ) Process can be omitted.

As described above, in the process of distributing the plurality of oxide particles 110P to form the plurality of irregularities on the first electrode 110, compared with the process of etching the plurality of irregularities on the first electrode 110 It is not only simple and time-consuming, but also it is not necessary to etch a part of the deposited first electrode 110, which can reduce processing time and manufacturing cost.

2, incident light can be scattered twice on the surface of the first electrode 110 on the substrate 100 side and on the surface of the photoelectric conversion portion PV, And the light of the longer wavelength band can be absorbed by the photoelectric conversion unit (PV). Therefore, the efficiency of the solar cell can be further increased.

8, a photoelectric conversion unit PV, a rear reflective layer 130, and a second electrode 140 may be sequentially formed on the first electrode 110.

Here, the photoelectric conversion unit PV may have one or a plurality of photoelectric conversion layers for forming the p-i-n semiconductor layers in the same structure as described in Figs. 1 and 3 and 4.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.

Claims (18)

Board;
A first electrode disposed on the substrate;
A photoelectric conversion unit disposed on the first electrode; And
And a second electrode disposed on the photoelectric conversion unit,
Wherein a plurality of oxide particles are positioned at an interface between the first electrode and the substrate. The method according to claim 1,
Wherein a refractive index of the plurality of oxide particles has a value between a refractive index of the substrate and a refractive index of the first electrode. The method according to claim 1,
Wherein the refractive index of the plurality of oxide particles has a value between 1.5 and 2.0. The method according to claim 1,
Wherein the size of the plurality of oxide particles is uneven. The method according to claim 1,
Wherein the plurality of oxide particles comprise first particles of a first size or larger and second particles smaller in size than the first particles. The method according to claim 1,
And the size of the plurality of oxide particles is between 5 nm and 500 nm. The method according to claim 1,
Wherein the plurality of oxide particles comprise a transparent material. The method according to claim 1,
Wherein the plurality of oxide particles comprise at least one of SiO ₂ , TiO ₂ , SiO x N y, and Al ₂ O ₃ . The method according to claim 1,
Wherein the surface of the first electrode facing the substrate comprises a plurality of irregularities. The method according to claim 1,
Wherein the thickness of the first electrode is between 500 nm and 1.5 占 퐉. The method according to claim 1,
Wherein the first electrode comprises a transparent conductive material. The method according to claim 1,
Wherein the first electrode comprises at least one of a ZnO-based material and a SnO-based material. The method according to claim 1,
The first electrode may be formed of at least one of zinc oxide (ZnOx), tin oxide (SnOx), indium oxide (InOx), zinc boron oxide (ZnO: B, BZO) and aluminum zinc oxide And a thin film solar cell. The method according to claim 1,
Wherein the photoelectric conversion portion includes at least one photoelectric conversion layer including a pin semiconductor layer. Dispersing and distributing a plurality of oxide particles on a substrate;
Forming a first electrode on the substrate on which the plurality of oxide particles are distributed;
Forming a photoelectric conversion portion on the first electrode; And
And forming a second electrode on the photoelectric conversion unit. 16. The method of claim 15,
The step of dispersing and distributing the plurality of oxide particles
Spraying a solution containing the plurality of oxide particles onto the substrate; And
And drying the solution containing the plurality of oxide particles sprayed on the substrate. 16. The method of claim 15,
Wherein the first electrode is formed by at least one of chemical vapor deposition (CVD), sputtering (PECVD), and sputtering. 16. The method of claim 15,
Wherein the step of etching the first electrode is omitted.

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