TWI412144B - Anti-reflection solar cell - Google Patents

Abstract

The invention discloses an anti-reflection solar cell. The anti-reflection solar cell comprises a front substrate, a front electrode layer, a photoconductive layer and a back electrode layer. The front substrate and the front electrode layer are pervious to light, wherein the photoconductive layer absorbs the light from the front substrate. At least one optic layer is provided on the side opposite to the front substrate of the back electrode layer. The optic layer refracts the light from the back substrate.

Description

Thin film solar cell

The present invention relates to a thin film solar cell, and more particularly to a thin film solar cell used in a building glass curtain or a window glass, which has a special optical structure, so that when people look indoors, the light can be weakened. Not glaring.

The thin film solar cell is deposited on the substrate by using different films, and the layers of the film are divided by laser cutting to make them a single unit cell connected in series. The film deposited from the bottom to the top of the substrate is sequentially a front electrode, a light absorbing layer and a back electrode. In the prior art of a thin film solar cell, a solar cell has been disclosed in U.S. Patent No. 4,795,500. Referring to Figure 1A, the solar cell comprises a substrate 1, a light converting element 2 (including a front electrode layer 3, a photoreactive layer). 4 and the back electrode layer 5) and a resist layer 8 (resist layer), in the production of the solar cell, the resist layer 8 (resist layer) as a mask, and with an etching process (etching process) to form A plurality of light penetrating regions 6 are required.

In addition, another solar cell is disclosed in US Pat. No. 6,858,461. Referring to FIG. 1B, the solar cell 110 includes a substrate 114, a front electrode layer 118, a photoreactive layer 120 and a back electrode layer 122, which are cut by laser. In a manner, in a direction perpendicular to a groove 128 that divides the solar cell into unit cells 112 that are independently connected in series, a strip of scribe line 124 is cut while the metal back electrode layer is The 122 is removed to form a light penetrating region, so that the light source 116 can pass through the solar cell 110 to cause a transparent effect. In addition, another solar cell has been disclosed in U.S. Patent No. 2006/0112987. Referring to Figure 1C, a laser is used to remove the back electrode layer or the light absorbing layer to create a plurality of small holes 8 through which the entire film is made. Solar energy The battery module 19 has a plurality of light penetrating regions 18 for achieving transparency of the entire solar cell module 19.

The thin film solar cell formed above is a translucent thin film solar cell in order to absorb more sunlight and to create a plurality of light transmissive regions, but when used in actual situations, when people are looking indoors and outside, It is often felt that the sun is too glaring and inconvenient, so if it can invent a thin film solar cell that can absorb more sunlight on the one hand and inconvenience on the other hand, it is really needed by the industry.

In order to solve the above-mentioned prior art, the present invention provides a thin film solar cell and a method for fabricating the same, comprising at least sequentially forming a front substrate, a front electrode layer, a light absorbing layer and a back electrode layer. Wherein, the front substrate and the front electrode layer are both transparent materials, and the light absorbing layer mainly absorbs light incident from the front substrate, and the back electrode layer is provided with at least one optical layer opposite to one side of the front substrate, by the optical layer The optical microstructure is included to refract and reflect light to scatter and soften light incident from the back electrode layer opposite the front substrate.

Accordingly, the main object of the present invention is to provide a thin film solar cell in which at least one optical layer is disposed opposite to one side of the front substrate, and the optical layer is used to form an anti-reflective surface, which is transmitted through the optical layer. Light, which allows people to stay indoors and look out, the light can be soft and not glare.

Since the present invention discloses a thin film solar cell and a method for fabricating the same, the photoelectric conversion principle of the solar cell utilized therein is well known to those skilled in the relevant art, and therefore, the description below will not be completely described. At the same time, the drawings referred to in the following texts express the structural schematics related to the features of the present invention, and do not need to be completely drawn according to the actual size. System, 盍 first clarify.

Referring first to FIG. 2, a first preferred embodiment of the present invention is a schematic cross-sectional view of a thin film solar cell 20. The thin film solar cells 20 are sequentially stacked to form a front substrate 11, a front electrode layer 12, a light absorbing layer 13, and a back electrode layer 14. The front substrate 11 and the front electrode layer 12 are made of a light transmissive material, the front substrate 11 is a glass substrate, and the front electrode layer 12 can be a single layer structure or a multilayer transparent oxide (TCO: Transparent Conductive Oxide). ), and its optional materials are tin dioxide (SnO ₂ ), indium tin oxide (ITO), zinc oxide (ZnO), aluminum zinc oxide (AZO), gallium tin oxide (GZO) or indium zinc oxide (IZO). The light absorbing layer 13 may be composed of a single structure or a multilayer structure, and the material selected from the group consisting of a crystalline germanium semiconductor, an amorphous germanium semiconductor, a semiconductor compound, an organic semiconductor, or a sensitizing dye; The electrode layer 14 may be composed of a single structure or a multi-layer structure, and further includes a metal layer, and the metal layer may be selected from the group consisting of silver (Ag), aluminum (Al), chromium (Cr), titanium (Ti), and nickel (Ni). Or a metal such as gold (Au), in addition, the back electrode layer 14 further comprises a transparent conductive oxide, the optional material of which is tin dioxide (SnO ₂ ), indium tin oxide (ITO), zinc oxide (ZnO), oxidation A material composed of aluminum zinc (AZO), gallium zinc oxide (GZO), or indium zinc oxide (IZO).

In the above embodiment, the light absorbing layer 13 mainly absorbs light incident from the front substrate 11, and the back electrode layer 14 is provided with at least one optical layer 15 opposite to one side of the front substrate 11, for scattering from the back electrode layer 14 The light incident in the direction of the front substrate 11 enables the thin film solar cell 20 to achieve the scattering effect of the light 31 by the interfacial refraction and the interface reflection formed by the light 31 passing between the microstructures of the organic materials. The organic material is composed of a polymer resin, a polymer rubber, or other organic material such as a transparent or opaque material having a refractive index larger than that of air. Of course, the thin film solar cell 20 can also achieve the effect of scattering of the light 31 by the interfacial refraction and the interface reflection formed by the light 31 passing through the microstructures of the inorganic materials, wherein the inorganic materials are tantalum rubber and tantalum resin. , cerium oxide, aluminum oxide, It is composed of an inorganic material such as titanium oxide or zinc oxide.

Referring to FIG. 3, the optical layer 15 may be doped with a plurality of micro-particles 151, and the interfacial refraction and interfacial reflection formed by the light rays 31 passing between the micro-particles 151 may achieve the effect of light scattering. The average particle diameter of the microparticles 151 is between 1 nm and 1000 μm. Referring to FIG. 4, the optical layer 15 can also be coated on the surface of the back electrode layer 14 opposite to the front substrate 11 to further form a rough surface 152 having a particle shape, thereby achieving the effect of light scattering, wherein the rough surface The roughness Ra of 152 is greater than 10 nm. The above-mentioned changes in the optical layer 15 can utilize the refraction of light, such as the microstructure of the organic material, the microstructure of the inorganic material, the fine particles 151 or the rough surface 152 having a particle shape, and can be scattered and softened. The light that penetrates the optical layer 15 allows the light to be soft and not glare when viewed indoors.

Please refer to FIG. 5, which is a schematic cross-sectional view of a second preferred embodiment of the present invention, which is a thin film solar cell 20 which can be used in a building glass curtain or a window. The thin film solar cells 20 are sequentially stacked to form a front substrate 11, a front electrode layer 12, a light absorbing layer 13, a back electrode layer 14, and a back substrate 16. The back substrate 16 is provided with at least one optical layer 15 opposite to one side of the front substrate 11 for scattering light incident from the back substrate 16 opposite to the front substrate 11. It is preferable to use a glass substrate for the back substrate 16, and of course, other light-transmitting materials may be used. Other features of the thin film solar cell 20, such as the front substrate 11, the front electrode layer 12, the light absorbing layer 13, the back electrode layer 14, and the optical layer 15, are as disclosed in the first preferred embodiment described above.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The above description should be understood and implemented by those skilled in the art, and thus the other disclosures are not disclosed. Equivalent changes or modifications made in the spirit of the invention shall be included in the scope of the patent application.

1 (prior art), 114 (prior art) ‧ ‧ substrate

2 (Prior technology) ‧‧‧Light conversion components

3 (prior art), 118 (prior art) ‧ ‧ front electrode layer

4 (prior art), 120 (prior art) ‧ ‧ light reaction layer

5 (prior art), 122 (prior art) ‧ ‧ rear electrode layer

6 (prior art), 18 (prior art) ‧ ‧ light penetration area

8 (prior art) ‧ ‧ impedance layer

110 (prior art) ‧ ‧ solar cells

112 (prior art) ‧‧‧unit block

116 (previous technique) ‧ ‧ light source

128 (prior art) ‧‧ ‧ wire trough

124 (prior art) ‧‧ cutting line

19 (previous technology) ‧ ‧ solar battery module

8 (previous technique) ‧ ‧ small holes

20‧‧‧Thin solar cells

11‧‧‧ front substrate

12‧‧‧ front electrode layer

13‧‧‧Light absorbing layer

14‧‧‧Back electrode layer

15‧‧‧Optical layer

151‧‧‧Microparticles

152‧‧‧Rough surface

16‧‧‧Back substrate

31‧‧‧Light

Figure 1A is a schematic view of the prior art of thin film solar cells.

Figure 1B is a schematic view of the prior art of thin film solar cells.

Figure 1C is a schematic view of the prior art of thin film solar cells.

2 is a schematic view showing a thin film solar cell according to a first preferred embodiment of the present invention.

Figure 3 is a schematic view showing a first preferred embodiment according to the present invention as a thin film solar cell.

Figure 4 is a schematic view showing a first preferred embodiment according to the present invention as a thin film solar cell.

Fig. 5 is a schematic view showing a second preferred embodiment according to the present invention as a thin film solar cell.

20‧‧‧Thin solar cells

11‧‧‧ front substrate

12‧‧‧ front electrode layer

13‧‧‧Light absorbing layer

14‧‧‧Back electrode layer

15‧‧‧Optical layer

31‧‧‧Light

Claims (29)

A thin film solar cell comprising at least a front substrate, a front electrode layer, a light absorbing layer and a back electrode layer, wherein the front substrate and the front electrode layer are both transparent materials, and the light absorbing layer is mainly absorbed from the The light of the front substrate is opposite to the side of the front substrate, at least one optical layer is disposed, and the optical layer mainly includes a plurality of microstructures, and the interface formed by the light passing through the microstructures Refraction and interfacial reflection to scatter light incident from the back electrode layer in a direction opposite to the front substrate. The thin film solar cell of claim 1, wherein the microstructure of the optical layer is mainly an organic material selected from the group consisting of a polymer resin, a polymer rubber, or the like. group. The thin film solar cell according to claim 1, wherein the microstructure of the optical layer is mainly an inorganic material selected from the group consisting of ruthenium rubber, ruthenium oxide, ruthenium oxide, aluminum oxide, titanium oxide and zinc oxide. . The thin film solar cell of claim 1, wherein the optical layer has a microstructure mainly composed of fine particles having an average particle diameter of between 1 nm and 1000 μm. The thin film solar cell of claim 1, wherein the optical layer achieves light scattering by coating the surface of the back electrode layer opposite to the front substrate to form a structure having a particulate rough surface. A thin film solar cell according to claim 5, wherein the roughness of the rough surface is greater than 10 nm. The thin film solar cell according to the first aspect of the invention, wherein the material of the front electrode layer is a transparent conductive oxide (TCO: Transparent Conductive Oxide), the material of which is selected from the group consisting of tin dioxide (SnO ₂ ) and indium oxide. A group consisting of tin (ITO), zinc oxide (ZnO), aluminum zinc oxide (AZO), gallium tin oxide (GZO), and indium zinc oxide (IZO). The thin film solar cell of claim 1, wherein the front electrode layer may be a single layer structure or a multilayer structure. The thin film solar cell of claim 1, wherein the light absorbing layer may be a single layer structure or a multilayer structure. The thin film solar cell according to claim 1, wherein the material of the light absorbing layer is selected from the group consisting of a crystalline germanium semiconductor, an amorphous germanium semiconductor, a semiconductor compound, an organic semiconductor, a sensitizing dye, and the like. The thin film solar cell of claim 1, wherein the back electrode layer further comprises a metal layer selected from the group consisting of silver (Ag), aluminum (Al), chromium (Cr), and titanium (Ti). A group consisting of nickel (Ni) and gold (Au). The thin film solar cell of claim 1, wherein the back electrode layer further comprises a transparent conductive oxide selected from the group consisting of tin dioxide (SnO ₂ ), indium tin oxide (ITO), and zinc oxide ( A group consisting of ZnO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), and indium zinc oxide (IZO). The thin film solar cell of claim 1, wherein the back electrode layer may be a single layer structure or a multilayer structure. The thin film solar cell of claim 1, wherein the front substrate is a glass substrate. A thin film solar cell comprising at least a front substrate, a front electrode layer, a light absorbing layer, a back electrode layer and a back substrate, wherein the front substrate and the front electrode layer are both transparent materials, and the light absorbing layer is mainly Absorbing light incident from the front substrate, the back substrate is disposed at least opposite to one side of the front substrate with an optical layer, the optical layer mainly includes a plurality of microstructures formed by light passing between the microstructures The interface is refracted and the interface is reflected to scatter light incident from the back substrate opposite to the front substrate. A thin film solar cell according to claim 15 wherein the microstructure of the optical layer is mainly an organic material selected from the group consisting of a polymer resin, a polymer rubber, or the like. group. A thin film solar cell according to claim 15 wherein the microstructure of the optical layer is mainly an inorganic material selected from the group consisting of ruthenium rubber, ruthenium oxide, ruthenium oxide, aluminum oxide, titanium oxide and zinc oxide. . A thin film solar cell according to claim 15 wherein the microstructure of the optical layer is mainly microparticles having an average particle diameter of between 1 nm and 1000 μm. The thin film solar cell of claim 15, wherein the optical layer achieves light scattering by coating the surface of the back electrode layer opposite to the front substrate to form a structure having a particulate rough surface. A thin film solar cell according to claim 19, wherein the roughness of the rough surface is greater than 10 nm. The thin film solar cell according to claim 15 , wherein the material of the front electrode layer is a transparent conductive oxide (TCO: Transparent Conductive Oxide), the material of which is selected from the group consisting of tin dioxide (SnO ₂ ) and indium oxide. A group consisting of tin (ITO), zinc oxide (ZnO), aluminum zinc oxide (AZO), gallium tin oxide (GZO), and indium zinc oxide (IZO). The thin film solar cell of claim 15, wherein the front electrode layer may be a single layer structure or a multilayer structure. A thin film solar cell according to claim 15 wherein the light absorbing layer is a single layer structure or a multilayer structure. The thin film solar cell according to claim 15, wherein the material of the light absorbing layer is selected from the group consisting of a crystalline germanium semiconductor, an amorphous germanium semiconductor, a semiconductor compound, an organic semiconductor, a sensitizing dye, and the like. A thin film solar cell according to claim 15 wherein the back electrode layer is further A metal layer is included, the material of which is selected from the group consisting of silver (Ag), aluminum (Al), chromium (Cr), titanium (Ti), nickel (Ni), and gold (Au). The thin film solar cell of claim 15, wherein the back electrode layer further comprises a transparent conductive oxide selected from the group consisting of tin dioxide (SnO ₂ ), indium tin oxide (ITO), and zinc oxide ( A group consisting of ZnO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), and indium zinc oxide (IZO). The thin film solar cell of claim 15, wherein the back electrode layer may be a single layer structure or a multilayer structure. A thin film solar cell according to claim 15 wherein the front substrate is a glass substrate. A thin film solar cell according to claim 15 wherein the back substrate is a glass substrate.