TWM587827U - Thin film solar cell - Google Patents

Abstract

A thin film solar cell including a transparent substrate, a solar cell unit, a plurality of insulating layers and a conductive layer. The transparent substrate includes a center region and a peripheral region surrounding the center region. The solar cell unit includes a front electrode layer, a photovoltaic conversion layer and a back electrode layer. The front electrode layer is disposed on the transparent substrate. The photovoltaic conversion layer is disposed on the front electrode layer. The back electrode layer is disposed on the photovoltaic conversion layer. The plurality of insulating layers covers the back electrode layer and exposes a portion of the front electrode layer. The plurality of insulating layers include at least a first insulating layer and a second insulating layer in this order. The first insulating layer includes an inorganic material. The second insulating layer includes an organic material. The conductive layer is disposed on the insulating layer and is electrically connected to the front electrode layer.

Description

Thin film solar cell

The novel creation relates to a thin-film solar cell, and more particularly to a cladding-type thin-film solar cell.

Thin-film solar cells can be divided into superstrate thin-film solar cells and substrate-type solar cells according to the incident direction of ambient light. In a cladding-type thin-film solar cell, after the ambient light penetrates the transparent substrate, it can excite the semiconductor material in the photoelectric conversion layer to generate multiple electron-hole pairs. The electrons and holes each pass through the front electrode layer and the back electrode layer. Collect to generate current.

In order to lead out the holes of the front electrode layer at the interlayer of the cladding-type thin-film solar cell, a conductive layer electrically connected to the front electrode layer is provided above the back electrode layer. The conductive layer covers the back electrode layer. The insulating layer is electrically insulated from the back electrode layer. However, the material included in this insulating layer will affect the conversion efficiency of thin-film solar cells. When the insulating layer includes inorganic materials, it has a relatively high dielectric constant and can have a thin thickness. It also has the ability to block water and oxygen and reduce leakage. The advantage of current, but also has high parasitic capacitance; when the insulating layer includes organic materials, it has a relatively low dielectric constant and can have low parasitic capacitance, but its ability to block water and oxygen is poor and susceptible to temperature And change the electrical properties.

This novel creation provides a thin-film solar cell with improved conversion efficiency.

The novelly-created thin-film solar cell includes a transparent substrate, a solar battery cell, a plurality of layers of insulating layers, and a conductive layer. The transparent substrate includes a central region and a peripheral region surrounding the central region. The solar cell includes a front electrode layer, a photoelectric conversion layer, and a back electrode layer. The front electrode layer is disposed on a transparent substrate. The photoelectric conversion layer is disposed on the front electrode layer. The back electrode layer is disposed on the photoelectric conversion layer. A plurality of insulating layers cover the back electrode layer and the exposed part of the front electrode layer. The plurality of insulating layers includes at least a first insulating layer and a second insulating layer that are sequentially stacked. The first insulating layer includes an inorganic material, and the second insulating layer includes an organic material. The conductive layer is disposed on the insulating layer and is electrically connected to the front electrode layer.

In an embodiment of the present invention, the plurality of insulating layers cover the top surface of the back electrode layer and the side surfaces of the back electrode layer and the photoelectric conversion layer.

In an embodiment of the present invention, the thickness of the first insulating layer is 0.2 μm to 0.6 μm.

In an embodiment of the present invention, the thickness of the second insulating layer is 2 μm to 4 μm.

In an embodiment of the present invention, the inorganic material includes silicon nitride (SiN _x ).

In an embodiment of the present invention, the material of the front electrode layer includes zinc oxide aluminum (AZO), zinc boron oxide (BZO), or tin oxide (SnO ₂ ).

In an embodiment of the present invention, a material of the photoelectric conversion layer includes single crystal silicon, polycrystalline silicon, amorphous silicon, or a combination thereof.

In an embodiment of the present invention, the material of the back electrode layer includes molybdenum tantalum (MoTa) or a combination of molybdenum tantalum and aluminum.

In an embodiment of the present invention, the material of the conductive layer includes molybdenum tantalum or a combination of molybdenum tantalum and aluminum.

Based on the above, the thin film solar cell created by the present invention can improve the electrical property of the solar cell by providing a plurality of insulating layers including a combination of an inorganic material and an organic material between the back electrode layer and the conductive layer. Increase the conversion efficiency of thin-film solar cells.

In order to make the above-mentioned features and advantages of the novel creation more comprehensible, embodiments are described below in detail with the accompanying drawings as follows.

Reference will now be made in detail to the exemplary embodiments of the present novelty, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. The novel creation can also be embodied in various forms and should not be limited to the embodiments described herein. The thicknesses of layers and regions in the drawings are exaggerated for clarity. The same or similar reference numbers indicate the same or similar elements, and the following paragraphs will not be repeated one by one. In addition, the directional terms mentioned in the embodiments, such as: up, down, left, right, front, or back, are only directions referring to the drawings. Therefore, the terminology used is used to explain and is not used to limit the novel creation.

FIG. 1 is a schematic top view of a thin film solar cell according to an embodiment of the novel creation. FIG. 2 is a schematic enlarged cross-sectional view of an embodiment of the thin-film solar battery cell in FIG. 1.

Please refer to FIG. 1 and FIG. 2 at the same time. The thin film solar cell 10 of this embodiment includes a transparent substrate 100, a solar cell unit 200, a plurality of insulating layers 300, and a conductive layer 400.

The solar battery cell 200 is provided, for example, in a partial region on one side of the transparent substrate 100. In detail, the thin-film solar cell 10 of this embodiment is, for example, a cladding-type thin-film solar cell. The above-mentioned thin-film solar cell means that the ambient light L is irradiated to the side of the transparent substrate 100 on which the solar cell unit 200 is not provided, and penetrates the transparent substrate 100 and enters the inside of the solar cell unit 200. In one embodiment, the material of the transparent substrate 100 may be glass, transparent resin, or other suitable transparent materials. The transparent resin may be, for example, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyether, or polyimide. In this embodiment, the material of the transparent substrate 100 is glass.

From another perspective, the thin-film solar cell 10 has a central region 10 a and a peripheral region 10 b, as shown in FIG. 1. For example, the transparent substrate 100 is comprehensively provided in the central region 10a and the peripheral region 10b, and the solar battery cells 200 are also comprehensively provided in the peripheral region 10b. The solar battery cells 200 are provided in the center region 10 a in, for example, a plurality of linear patterns. It should be particularly noted that although the thin film solar cell 10 of this embodiment is rectangular in shape, the novel creation is not limited to this. For example, the shape of the thin-film solar cell 10 in this embodiment may also be circular or other geometric shapes.

The thin-film solar cell 10 of this embodiment can be applied to a display (not shown). For example, the thin-film solar cell 10 of this embodiment may be disposed on one side of a display surface of a display panel (not shown), wherein the central region 10a of the thin-film solar cell 10 corresponds to, for example, the display region of the display panel, and the thin-film solar cell 10 The peripheral region 10 b of the battery 10 corresponds to, for example, a non-display region of a display panel. Based on this, since the central region 10a of the thin-film solar cell 10 is mostly the transparent substrate 100, it is possible to prevent the screen displayed on the display panel from being hindered.

Referring to FIG. 2, the solar battery cell 200 includes, for example, a front electrode layer 210, a photoelectric conversion layer 220, and a back electrode layer 230 sequentially stacked on the transparent substrate 100.

The front electrode layer 210 is provided on the transparent substrate 100, for example. The method of forming the front electrode layer 210 is, for example, a sputtering method, but the novel creation is not limited thereto. The material of the front electrode layer 210 is, for example, a transparent conductive oxide (Transparent Conductive Oxide; TCO). For example, the material of the front electrode layer 210 includes zinc oxide aluminum (AZO), zinc boron oxide (BZO), or tin oxide (SnO ₂ ). In this embodiment, the material of the front electrode layer 210 is selected from alumina zinc.

The photoelectric conversion layer 220 is disposed on the front electrode layer 210, for example. The method for forming the photoelectric conversion layer 220 is, for example, a chemical vapor deposition method, but the novel creation is not limited thereto. In one embodiment, the material of the photoelectric conversion layer 220 may include single crystal silicon, polycrystalline silicon, or amorphous silicon, that is, the thin film solar cell 10 of this embodiment may be a silicon thin film solar cell. In this embodiment, the material of the photoelectric conversion layer 220 is amorphous silicon. The photoelectric conversion layer 220 includes, for example, a first extrinsic semiconductor layer 220a, an intrinsic semiconductor layer 220b, and a second extrinsic semiconductor layer 220c that are sequentially stacked. The first extrinsic semiconductor layer 220a has a first doping type. And the second extrinsic semiconductor layer 220c has a second doping type. The first doping type and the second doping type are one of a P-type and an N-type. In this embodiment, the first doping type is P-type and the second doping type is N-type, but the novel creation is not limited to this.

The back electrode layer 230 is disposed on, for example, the photoelectric conversion layer 220 and is in contact with the second extrinsic semiconductor layer 220c. The method of forming the back electrode layer 230 is, for example, a sputtering method or a chemical vapor deposition method, but the novel creation is not limited thereto. The material of the back electrode layer 230 is, for example, a metal, an alloy, or a metal oxide. For example, the material of the back electrode layer 230 includes molybdenum tantalum (MoTa) or a combination of molybdenum tantalum and aluminum. In this embodiment, the material of the back electrode layer 230 is a combination of molybdenum tantalum and aluminum.

In this embodiment, the photoelectric conversion layer 220 and the back electrode layer 230 expose a part of the front electrode layer 210. In detail, the plurality of photoelectric conversion layers 220 and the back electrode layer 230 are formed on the front electrode layer 210 and are dispersed, for example.

The plurality of insulating layers 300 cover, for example, the back electrode layer 230 and the front electrode layer 210 of an exposed portion. In detail, the plurality of insulating layers 300 cover at least the top surface of the back electrode layer 230 and the side surfaces of the back electrode layer 230 and the photoelectric conversion layer 220. The method for forming the plurality of insulating layers 300 is, for example, formed by using a physical vapor deposition method or a chemical vapor deposition method and then performing a lithography etching process. For example, a plurality of insulating material layers (not shown) can be sequentially deposited on the transparent substrate 100 by using a physical vapor deposition method or a chemical vapor deposition method. Next, a patterned photoresist layer (not shown) is formed on the multilayer insulating material layer. After that, the patterned photoresist layer is used as a mask, and an etching process is performed on the multiple insulating material layers to form a plurality of insulating layers 300. In one embodiment, at least one of the plurality of insulating layers 300 includes an inorganic material, and at least one of the plurality of insulating layers 300 includes an organic material. The foregoing inorganic material may be, for example, silicon nitride (SiNx), silicon dioxide (SiO ₂ ), or aluminum oxide (Al ₂ O ₃ ), and the foregoing organic material may be, for example, pentacene, diethyl Glycol dimethyl ether (DEDM) or polyimide. In addition, a thickness T1 of one of the plurality of insulating layers 300 including an inorganic material is 0.2 μm to 0.6 μm, and a thickness T2 of another of the plurality of insulating layers including an organic material is 2 μm to 4 μm. When one of the plurality of insulating layers 300 includes an inorganic material, it has the advantages of blocking water and oxygen and reducing leakage, and when the other layer of the plurality of insulating layers 300 includes an organic material, it has a low dielectric constant. The generated parasitic capacitance is small, and has high flatness to facilitate subsequent processes.

In this embodiment, the plurality of insulating layers 300 includes a first insulating layer 310 and a second insulating layer 320 that are sequentially stacked. The first insulating layer 310 includes, for example, silicon nitride and has a thickness T1 of 0.5 μm. The second insulating layer 320 includes, for example, diethylene glycol dimethyl ether (DEDM) and the like, and has a thickness T2 of 3 micrometers. As shown in FIG. 2, the first insulating layer 310 and the second insulating layer 320 both cover the top surface of the back electrode layer 230 and the side surfaces of the back electrode layer 230 and the photoelectric conversion layer 220, but it should be noted that the novel creation is not limited to this . In another embodiment, the first insulating layer 310 covers the top surface of the back electrode layer 230 and the side surfaces of the back electrode layer 230 and the photoelectric conversion layer 220, and the second insulating layer 320 only covers the top surface of the back electrode layer 230. In yet another embodiment, the first insulating layer 310 covers only the top surface of the back electrode layer 230, and the second insulating layer 320 covers the top surface of the back electrode layer 230 and the side surfaces of the back electrode layer 230 and the photoelectric conversion layer 220.

The conductive layer 400 is disposed on, for example, a plurality of insulating layers 300 and is electrically connected to the front electrode layer 210 exposed by the plurality of insulating layers 300. In detail, a part of the conductive layer 400 is formed on the sidewalls of the plurality of insulating layers 300 to be electrically connected to the front electrode layer 210. The method for forming the conductive layer 400 is, for example, a sputtering method or a chemical vapor deposition method, but the novel creation is not limited thereto. The material of the conductive layer 400 is, for example, a metal, an alloy, or a metal oxide. For example, the material of the conductive layer 400 includes molybdenum tantalum (MoTa) or a combination of molybdenum tantalum and aluminum. In this embodiment, the material of the conductive layer 400 is a combination of molybdenum and tantalum and aluminum. In this embodiment, the conductive layer 400 is formed in the central region 10 a of the thin-film solar cell 10. The conductive layer 400 can be used for further quickly deriving the holes collected by the front electrode layer 210 located in the central region 10a, so as to avoid recombination of the electron-hole pairs and reduce the conversion efficiency of the solar battery cell 200. In addition, the conductive layer 400 is provided corresponding to the front electrode layer 210 in the central region 10a, that is, the orthographic projection of the conductive layer 400 substantially falls in the region of the front electrode layer 210, so the arrangement of the conductive layer 400 can be avoided and The transmittance of the central region 10a of the thin-film solar cell 10 is destroyed.

In one embodiment, the thin-film solar cell 10 further includes a protective layer (not shown) disposed on the transparent substrate 100, and the protective layer (not shown) covers the conductive layer 400. The material of the protective layer (not shown) may be an inorganic material, an organic material, or a combination thereof. The limitation is that the material needs to be transparent. In this embodiment, the protective layer (not shown) is made of an organic material. The protective layer (not shown) is used to protect the conductive layer 400 from the external environment.

In summary, the thin-film solar cell created by the present invention can improve the electrical property of the solar cell by providing a plurality of insulating layers including a combination of inorganic materials and organic materials between the back electrode layer and the conductive layer. This is to increase the conversion efficiency of thin film solar cells. In addition, the thin-film solar cell created by the new model can also quickly export the holes collected by the front electrode layer by placing a conductive layer on the outside of the solar cell in the central area to avoid most of the electron-hole pairs. Recombination improves the conversion efficiency of solar cells. In addition, since the conductive layer created in the present invention is provided corresponding to the front electrode layer in the central region, the transmittance of the central region of the thin-film solar cell may not be reduced.

Although this new type of creation has been disclosed as above by way of example, it is not intended to limit the new type of creation. Any person with ordinary knowledge in the technical field can make some changes without departing from the spirit and scope of this new type of creation Retouching, so the protection scope of this new type of creation shall be determined by the scope of the attached patent application.

10‧‧‧ thin film solar cell
10a‧‧‧ central area
10b‧‧‧ Outer area
100‧‧‧ transparent substrate
200‧‧‧solar cell
210‧‧‧ front electrode layer
220‧‧‧photoelectric conversion layer
220a‧‧‧The first extrinsic semiconductor layer
220b‧‧‧ intrinsic semiconductor layer
220c‧‧‧Second Extrinsic Semiconductor Layer
230‧‧‧ back electrode layer
300‧‧‧Plural layers of insulation
310‧‧‧First insulation layer
320‧‧‧Second insulation layer
400‧‧‧ conductive layer
L‧‧‧ Ambient light
T1, T2‧‧‧thickness

FIG. 1 is a schematic top view of a thin film solar cell according to an embodiment of the novel creation.
FIG. 2 is a schematic enlarged cross-sectional view of an embodiment of the thin-film solar battery cell in FIG. 1.

Claims (9)

A thin-film solar cell includes:
A transparent substrate including a central region and a peripheral region surrounding the central region;
Solar battery cells, including;
A front electrode layer disposed on the transparent substrate;
A photoelectric conversion layer is disposed on the front electrode layer; and a back electrode layer is disposed on the photoelectric conversion layer;
A plurality of insulating layers covering the back electrode layer and exposed portions of the front electrode layer, wherein the plurality of insulating layers include at least a first insulating layer and a second insulating layer sequentially stacked, the first insulating layer It includes the inorganic material, and the second insulation layer includes the organic material; and a conductive layer is disposed on the plurality of insulation layers and is electrically connected to the front electrode layer. The thin-film solar cell according to item 1 of the patent application scope, wherein the plurality of insulating layers cover a top surface of the back electrode layer and side surfaces of the back electrode layer and the photoelectric conversion layer. The thin-film solar cell according to item 1 of the scope of patent application, wherein the thickness of the first insulating layer is 0.2 μm to 0.6 μm. The thin-film solar cell according to item 1 of the scope of patent application, wherein the thickness of the second insulating layer is 2 μm to 4 μm. The thin-film solar cell according to item 1 of the patent application scope, wherein the inorganic material includes silicon nitride (SiN _x ). The thin-film solar cell according to item 1 of the scope of patent application, wherein the material of the front electrode layer includes zinc aluminum oxide (AZO), zinc boron oxide (BZO), or tin oxide (SnO ₂ ). The thin-film solar cell according to item 1 of the patent application scope, wherein the material of the photoelectric conversion layer includes single crystal silicon, polycrystalline silicon, amorphous silicon, or a combination thereof. The thin-film solar cell according to item 1 of the patent application scope, wherein the material of the back electrode layer includes molybdenum tantalum (MoTa) or a combination of molybdenum tantalum and aluminum. The thin-film solar cell according to item 1 of the scope of patent application, wherein the material of the conductive layer includes molybdenum tantalum or a combination of molybdenum tantalum and aluminum.