Crystalline silicon PERC cell alkali polishing method not influencing front surface

Abstract

The invention belongs to the manufacturing technology of a photovoltaic solar cell and relates to a crystalline silicon PERC cell alkali polishing method not influencing the front surface. The method comprises the following steps: a) enabling an original silicon wafer to react for 160-180 s in a polishing solution, of which the KOH mass ratio is 10-20%, and the temperature is 78-83 DEG C, for polishing; b) plating a 100-120 nm SiNx film, serving as a mask, on the polished silicon wafer through PECVD; c) enabling the plated silicon wafer to be soaked in HF for 80-100s to remove the SiNx film plated on the front surface thoroughly; d) texturing the plate-removed silicon wafer in a texturing tank, of which the KOH mass ratio is 1.5-3%, and the temperature is 80-82 DEG C, the texturing time being 1100-1300 s; and e) finishing the follow-up steps by the textured silicon wafer according to a conventional PERC cell preparation method. The method can obtain a relatively-uniform polished surface, and meanwhile, can prevent causing influence on the front surface, thereby improving cell performance.

Description

technical field [0001] The invention belongs to the manufacturing technology of photovoltaic solar cells, and relates to an alkali polishing method for crystalline silicon PERC cells that does not affect the front surface. Background technique [0002] Solar photovoltaic power generation has great application prospects. The current development trend of the photovoltaic industry is to improve efficiency and reduce costs. However, the efficiency of conventional structural batteries has no room for improvement. High-efficiency crystalline silicon batteries have become the mainstream of market research and development. For various P-type high-efficiency batteries, only the back passivation technology can maximize the performance of the battery on the basis of equal cost. Products with this technology have high efficiency, high opening voltage, low packaging loss, and better low-light response. They are strategic products to seize the mainstream market. [0003] PERC battery bac...

AI Technical Summary

Problems solved by technology

However, under the process of first texturizing and then polishing, the alkali hanging on the polishing surface is more serious, resulting in uneven polishing surface; and in the process of polishing and mask removal, it will have a certain impact on the front side, affecting the response of the battery in the short-wave band