Preparation process of shallow junction solar battery

Abstract

The invention discloses a preparation process of a shallow junction solar battery. The preparation process of the shallow junction solar battery comprises the following steps: a. cleaning a silicon wafer, removing a damaged layer, and making herbs into wool; b. spraying phosphoric acid on the surface of the silicon wafer; c. putting the silicon wafer into a chain-type diffusion furnace, and diffusing; d. removing phosphorosilicate glass for the diffused silicon wafer and etching a surface dead layer; e. depositing silicon nitride on the surface of an emitting electrode and passivating an antireflection layer; f. carrying out silk-screen printing on a back electrode and a positive surface electrode or electroplating the positive surface electrode; and g. sintering, testing and sorting. The preparation process of the shallow junction solar battery guarantees that sheet resistance is distributed uniformly based on a shallow junction, has much low saturation current density of the emitting electrode, improves the short-wave response of the solar battery obviously, and improves the open circuit voltage and short circuit voltage of the solar battery.

Description

technical field [0001] The invention relates to a preparation process of a solar cell, in particular to a preparation process of a shallow junction solar cell. Background technique [0002] As human beings pay attention to climate issues, renewable energy is developing rapidly. Among them, photovoltaic, as an important renewable energy, has achieved leapfrog development in the past ten years. It is a new energy actively developed by developed countries and has endless development potential. [0003] The core step of producing solar cells is to prepare P-N junctions, but the current industrial scale production of solar cells still uses thermal diffusion to make junctions. The P-N junction method of thermal diffusion is to use the heating method to make V-type impurities doped into P-type silicon or III-type impurities into N-type silicon; impurity elements enter the matrix due to thermal diffusion movement at high temperature, and its distribution in the matrix depends on th...

AI Technical Summary

Problems solved by technology

[0006] Compared with the tubular diffusion method, after the chain diffusion process is diffused, the uniformity of the square resistance is better; the phosphoric acid as the diffusion source is more environmentally friendly and safe than the phosphorus oxychloride; the degree of automation is high, and it can be connected with the existing texturing and edge etching processes , which greatly improves the production capacity, reaching more than 2000 pieces / hr; the maintenance is simple in production, and compared with the tubular type, it does not need to do TCA or clean the quartz tube, and the continuous online cleaning greatly increases the production capacity and reduces the operating cost; however, chain diffusion After that, the surface concentration of phosphorus atoms is high and the dead layer is thick, which limits the improvement of its efficiency.