Preparation method of crystalline silicon solar cell

Abstract

The invention discloses a preparation method of a crystalline silicon solar cell. In the passivation process technology of the back surface of a silicon wafer, because aluminum oxide has constant negative charge, the composition of the back surface can be lowered, and the same time, because silicon nitride in rich in hydrogen, passivation can be realized effectively, and in addition, the passivation overlapping layers of aluminum oxide and silicon nitride act as a back reflector, the absorption of long beam waves can be improved greatly, the passivation overlapping layers are positioned between a back surface electrode and the silicon wafer, the warping degree of the crystalline silicon solar cell can be lowered greatly, and the influence on the lifetime of a minority carrier in the silicon wafer can be lowered effectively; and when the back surface electrode is manufactured, because the passivation overlapping layers for the corrosion depth in the corrosion region is just removed, the problem that the back surface electrode and the silicon wafer have less possibility of forming favorable ohmic contact due to the back surface passivation of the silicon wafer can be solved effectively, at the same time, a dense network structure is formed by connecting all the adjacent electric conducting materials by utilizing a silver wire, and the network structure is especially favorable for the collection and conduction of back surface current carriers of the silicon wafer.

Description

technical field [0001] The invention relates to a manufacturing process of a solar cell, in particular to a preparation method of a crystalline silicon solar cell. Background technique [0002] With the increasing shortage of conventional energy sources, renewable energy has been paid more and more attention by human beings. In the past ten years, the amount of solar power generation has shown an exponential growth. With the continuous improvement of the manufacturing process of solar cells and the continuous reduction of production costs, Solar cells will become more and more popular. [0003] At present, the manufacturing process of solar cells has been standardized. According to the production sequence of the process line, it is divided into the following steps: 1. Texturing the silicon wafer: through chemical reactions, the original bright silicon wafer surface (including the front and back) is formed into uneven texture. structure to extend the propagation path of lig...

AI Technical Summary

Problems solved by technology

These two back passivation methods have their drawbacks: in the first method, since the bulk minority carrier lifetime in silicon wafers is highly sensitive to high-temperature processes, especially polysilicon wafers, the thermal oxidation growth process above 900 °C will cause The bulk minority carrier lifetime in silicon wafers obviously declines; the second implementation method, the stacking of silicon nitride and silicon dioxide, is difficult to solve the warpage problem of crystalline silicon solar cells

On the other hand, the insulation of the back passivation structure blocks the silicon chip and the back electrode, resulting in the inability to form an ohmic contact between the silicon chip and the back electrode

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