CN102509749A - Texturing method for polycrystalline solar cell - Google Patents

Abstract

The invention discloses a method for preparing a suede surface on the surface of a silicon-based solar cell. Micro electric spark electrolysis is used to compositely process the polysilicon surface, and electrolysis is used as an auxiliary processing method while the suede structure is obtained by electric spark discharge to obtain a uniform suede surface. structure. The fine electric discharge electrode of the present invention can not only scan the polysilicon at high speed, but also enlarges the scanning range, and obviously improves the texturing efficiency. The prepared polysilicon can form a uniform micro-nano-scale suede structure, increase light absorption, reduce reflectivity, and is suitable for industrial production. The method can significantly reduce environmental pollution by chemical methods, improve efficiency and reduce the reflectivity of the suede surface.

Description

A kind of manufacturing method of textured surface of polycrystalline silicon solar cell

technical field

The invention relates to the preparation technology of polycrystalline silicon solar cells, in particular to a method for manufacturing the textured surface of polycrystalline silicon solar cells.

Background technique

Solar energy is an inexhaustible renewable resource for human beings, and it is also one of the clean energy sources that can be directly utilized. With the progress of society, the energy crisis and environmental pollution problems faced by human beings are becoming more and more serious. These problems have become the key points restricting the development of the global economy. The development and use of renewable, clean and environmentally friendly new energy is an inevitable trend of future social development. In recent years, solar cells have attracted widespread attention. Solar cells have many significant advantages, such as no pollution, energy available everywhere, and long service life. As a clean and non-polluting renewable resource that can efficiently convert light energy into electrical energy, the application of solar cells has entered the industry, agriculture, communications, household appliances, electric power and other sectors from the military and aerospace fields.

But at the current stage, the high production cost of solar cells and the low solar absorption rate limit the further development of solar cells. Therefore, how to reduce production costs, improve efficiency, and reduce reflectivity is still the main goal of solar cell research. The uniform surface suede structure increases the light absorption area and makes the incident light reflect multiple times on the surface, thereby greatly improving the solar energy absorption efficiency and reducing the light reflectivity. For polysilicon, its material is easy to manufacture, saves power consumption, and the total production cost is low. And as the production process of polysilicon continues to progress, its cost is much lower than that of monocrystalline silicon. Therefore, using a reasonable method to prepare a uniform textured structure of polysilicon can effectively reduce production costs and meet the existing demand for solar cells.

Existing surface texturing methods include chemical corrosion, electrochemical corrosion, mechanical grooving, ion etching and other technologies. Mechanical grooving technology, although the process is simple, but the efficiency is low, and the thickness of the silicon wafer required is not suitable for the manufacture of solar cells. Ion etching has complicated process, long production time, complex and expensive equipment, and is not suitable for industrial production. Chemical etching is currently a common method for manufacturing the textured structure of silicon wafers for solar cells. Although the production efficiency is high, it is difficult to obtain a uniform textured structure. Disadvantages such as large environmental pollution.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned deficiencies existing in the prior art, and to provide a method for manufacturing the suede surface of polycrystalline silicon solar cells. The preparation process is simple and convenient, and it is easy to realize industrial production. Texture-making efficiency can obtain micro-nano-scale textured structure.

The object of the invention is achieved through the following schemes:

A method for manufacturing the suede surface of a polycrystalline silicon solar cell, which uses micro-electric spark electrolysis to compositely process the polycrystalline silicon surface, and uses electrolysis as an auxiliary processing method to obtain a uniform suede structure when the electric spark discharge is used to obtain the suede structure, including the following step:

(1) Prepare polysilicon wafers and metal powder, and clean polysilicon wafers;

(2) Prepare an aluminum frame evenly arranged with magnets, connect the electrode shaft of the electric discharge machine tool to the aluminum frame; the aluminum frame is connected with the electrode shaft of the electric discharge machine tool through a sleeve, and the aluminum frame is ten Glyph, hexagon, circle or ring.

(3) Fix the polysilicon wafer on a stainless steel plate connected to a power supply, and place the aluminum frame in parallel with the polysilicon wafer. When working, the aluminum frame rotates and translates to scan the crystal silicon wafer. Tiny metal powder is adsorbed on the aluminum frame by a magnet. These The tiny metal powder is used as a tiny electrode during the processing process to generate a tiny electric spark, and as the spark discharge occurs between the aluminum frame and the polysilicon wafer, a high-temperature electrochemical action is generated in the composite working fluid, thereby realizing the spark electrolysis of the polysilicon wafer. A uniform micro-nano-scale suede structure is obtained;

(4) After finishing the textured surface of the polycrystalline silicon wafer, wash it with deionized water and dry it to prepare the textured surface of the polycrystalline silicon solar cell.

The metal powder is a micro-nano scale alloy powder, preferably the gold alloy powder is an iron-based or nickel-based alloy powder.

Compared with the prior art, the present invention has the following advantages and effects:

1. The fine EDM electrolytic composite texturing used in the present invention can directly obtain an ideal polysilicon textured structure, which is simple, convenient, and easy to realize industrial production.

2. The present invention adopts the aluminum frame with evenly arranged magnets to connect with the electrode shaft of the electric discharge machine tool. Its scanning range is large, the scanning speed is fast, the scanning is uniform, easy to control, and can obviously improve the texturing efficiency.

3. When the present invention is working, micro-nano metal powders are adsorbed on the aluminum frame with evenly arranged magnets. These micro-nano metal powders are used as tiny electrodes in the processing process to generate micro electric sparks to obtain a uniform textured structure. The finer the metal powder is, the more tiny electrodes are formed, and the better the effect of the polysilicon textured surface is.

Description of drawings

Fig. 1 is the relative position schematic diagram of the aluminum frame of the present invention that evenly arranges magnet and polysilicon sheet;

Fig. 2 is the schematic diagram of the light path of polysilicon uniform suede structure of the present invention;

Detailed ways

The present invention will be described in further detail below in conjunction with the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

Example

As shown in Fig. 1, the manufacturing method of polycrystalline silicon solar cell suede surface of the present invention, adopts micro electric spark electrolysis compound processing polysilicon surface, adopts electrolysis as auxiliary processing method when electric spark discharge makes suede structure, to obtain uniform suede Surface structure, including the following steps:

(1) Prepare polysilicon chip 3, metal powder, and clean polysilicon chip 3;

(2) Prepare an aluminum frame 2 evenly arranged with magnets, connect the electrode shaft 1 of the electric discharge machine tool to the aluminum frame 2; the aluminum frame 2 can be connected with the electrode shaft 1 through a sleeve (not shown in the figure ), the aluminum frame 2 is cross-shaped, hexagonal, circular or annular.

(3) Fix the polycrystalline silicon chip 3 on a stainless steel plate (not shown in the figure) connected to the power supply, and place the aluminum frame 2 in parallel with the polycrystalline silicon chip 3. During work, the aluminum frame 2 rotates and translates and scans the crystal silicon chip, and the tiny The metal powder is adsorbed on the aluminum frame 2 by a magnet. These tiny metal powders are used as tiny electrodes in the processing process to generate tiny electric sparks. As the spark discharge occurs between the aluminum frame 2 and the polysilicon wafer 3, in the composite working fluid High-temperature electrochemical action is generated, so as to realize electric spark electrolysis of polysilicon wafers to obtain uniform micro-nano-scale textured structures; the finer the metal powder, the more tiny electrodes formed, and the better the textured effect of polysilicon wafers.

(4) After finishing the textured surface of the polysilicon wafer 3, wash it with deionized water and dry it to prepare the textured surface of the polycrystalline silicon solar cell.

The metal powder is micro-nano scale alloy powder, and the gold alloy powder is preferably iron-based or nickel-based alloy powder.

A polycrystalline silicon solar cell with a textured surface can be obtained through the above method. The polysilicon prepared by the invention can form a uniform micro-nano-scale suede structure, increase light absorption, reduce reflectivity, and is suitable for industrial production. The surface texture method provided by the method can significantly reduce environmental pollution by chemical methods, improve efficiency, and reduce the reflectivity of the texture.

As described above, the present invention can be preferably carried out.

The above-mentioned embodiment is only a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (5)

1. the manufacturing approach of a polycrystalline silicon solar battery suede is characterized in that adopting fine electric spark electrolysis Compound Machining polysilicon surface, when spark discharge makes suede structure, adopts electrolysis as assistance processing method, to obtain uniform suede structure.

2. the manufacturing approach of polycrystalline silicon solar battery suede according to claim 1 is characterized in that comprising the steps:

(1) prepares polysilicon chip, metal dust, clean polysilicon chip;

(2) prepare one evenly be furnished with magnet aluminium chassis, the electrode axis of electric spark machine tool is connected on the aluminium chassis;

(3) polysilicon chip is fixed on the corrosion resistant plate that is connected to power supply; The parallel placement of aluminium chassis with polysilicon chip, during work, aluminium chassis rotation and translation scan crystal silicon sheet; Small metal dust is adsorbed on the aluminium chassis through magnet; These minute metallic powder as microelectrode, produce fine electric spark, along with the generation of sparkover between aluminium chassis and polysilicon chip in the course of processing; In compound working solution, produce the high-temperature electrochemistry effect, thereby realize that the polysilicon electric spark and electrolysis is to make the suede structure of uniform micro-nano-scale;

(4) behind the completion polysilicon chip matte, clean with deionized water, oven dry makes polycrystalline silicon solar battery suede.

2, the manufacturing approach of polycrystalline silicon solar battery suede according to claim 2 is characterized in that said metal dust is the alloy powder of micro-nano-scale.

3. the manufacturing approach of polycrystalline silicon solar battery suede according to claim 2 is characterized in that said billon powder is iron-based or Co-based alloy powder.

4. the manufacturing approach of polycrystalline silicon solar battery suede according to claim 2; It is characterized in that said aluminium chassis is connected with the electrode axis of electric spark machine tool through sleeve; Said aluminium chassis is cross, hexagon, circular or annular, and magnet is arranged on aluminium chassis inside uniformly.

5. according to the manufacturing approach of each described polycrystalline silicon solar battery suede in the claim 1～5, resulting polycrystalline silicon solar cell with matte.

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