High efficiency silicon-based heterojunction double-sided battery and its preparation method

Abstract

The invention discloses a high efficiency silicon-based heterojunction double-sided battery and its preparation method. The high efficiency silicon-based heterojunction double-sided battery comprises an N type silicon chip. On the front side of the N type silicon chip, a first intrinsic amorphous silicon layer, a second intrinsic amorphous silicon layer, a P type doped amorphous silicon layer, a transparent conductive film layer and a metal gate wire electrode are arranged in succession. The electron band gap of the second intrinsic amorphous silicon layer is greater than that of the first intrinsic amorphous silicon layer. On the back side of the N type silicon chip, a third intrinsic amorphous silicon layer, an N type doped amorphous silicon layer, a transparent conductive film layer and a metal gate wire electrode are arranged in succession. According to the invention, the first intrinsic amorphous silicon layer and the second intrinsic amorphous silicon layer are prepared in different chambers respectively, and the preparation temperature of the first intrinsic amorphous silicon layer is lower than that of the second intrinsic amorphous silicon layer so that the second intrinsic amorphous silicon layer has a relatively wider electron band gap which corresponds to the band gap of a crystalline silicon and therefore, can be used as a barrier layer to block the diffusion of electrons into the emitter using the difference in band width; therefore, the combination of electrons with empty cavities can be reduced, improving the electrical performance of the battery.

Description

technical field [0001] The invention relates to the field of solar cells, in particular to a high-efficiency silicon-based heterojunction double-sided cell and a preparation method thereof. Background technique [0002] A thin film solar cell is a solar cell formed by depositing a thin photoelectric material on a substrate. Thin-film solar cells can still generate electricity under weak light conditions, and their production process consumes less energy, which has the potential to greatly reduce raw material and manufacturing costs. Therefore, the market demand for thin-film solar cells is gradually increasing, and thin-film solar cell technology has become a research hotspot in recent years. Among them, improving photoelectric conversion efficiency and reducing costs are the ultimate goals of the solar industry. [0003] Silicon-based solar cells have become more attractive in recent years as the cost of the silicon material has decreased. To improve the conversion effic...

AI Technical Summary

Problems solved by technology

Due to the high self-built electric field, it is easier to separate the carriers generated in the PN junction and in the crystalline silicon, that is, electrons and holes. However, due to the diffusion of electrons, electrons will also move to the emitter, resulting in electrons and holes being separated. The recombination of the emitter region reduces the short-circuit current of the cell and reduces the photoelectric conversion efficiency of the cell, that is, the output power

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