Preparation method of selective doping structure of solar cell

Abstract

The invention belongs to the technical field of solar cells, and relates to a preparation method of a selective doping structure of a solar cell; the method comprises the following steps: step 1, pretreating the surface of a silicon wafer, and depositing a poly layer containing a doping source on the surface of the pretreated silicon wafer; step 2, carrying out laser processing on a part of the surface of the poly layer to form a heavily doped region; step 3, annealing the silicon wafer to form a lightly doped region in a non-laser-treated region on the surface of the poly layer, and introducing O2-containing gas in the annealing treatment process to oxidize the poly layer into a BSG / PSG layer; and step 4, cleaning the silicon wafer to remove the BSG / PSG layer so as to obtain the selective doping structure of the solar cell. According to the preparation method, the doping amounts of the lightly doped region and the heavily doped region of the selective doping structure can be accurately controlled, the preparation process and structure can be simplified, and the preparation efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of solar cells, in particular to a method for preparing a selective doping structure of a solar cell. Background technique [0002] Solar cells refer to devices that use semiconductor silicon, selenium and other materials to convert effectively absorbed solar energy into electrical energy. Because of its high reliability, long life, and high conversion efficiency, it is widely used as a power source for artificial satellites and navigation lights. [0003] Among them, the junction depth and impurity concentration of the surface of the traditional crystalline silicon solar cell are the same everywhere, therefore, uniform doping on the surface of the silicon wafer is sufficient. However, this structure greatly limits the improvement of the conversion efficiency of solar cells, as follows: when the doping concentration of the electrode contact area is low, the contact resistance between the metal electrode and...

AI Technical Summary

Problems solved by technology

However, in this preparation method, the formation of the heavily doped region and the lightly doped region needs to rely on the three-layer structure of the barrier layer, the first impurity source layer and the second impurity source layer, resulting in a complex structure, which leads to its preparation process It is more complicated and cumbersome, which prolongs its preparation time and affects the preparation efficiency

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