A kind of preparation method of n-type single crystal double-sided battery

Abstract

The invention discloses a preparation method for an N-type single-crystal double-faced battery which is high in wafer forming ratio and good in photoelectric conversion efficiency. The method comprises the steps of performing texturing on a front surface of a silicon wafer and carrying out B diffusion, wherein the steps of the front surface texturing comprises the steps of forming a pyramid structure on the front surface of the silicon wafer by employing laser, after nitrogen is cleaned, heating the silicon wafer to 70-80 degrees centigrade, depositing NaOH droplets on the front surface of the silicon wafer through ultrasonic atomization, and forming a pyramid texture structure after corrosion is carried out for 2-4 minutes; carrying out wet etching to remove self-diffusion layers formed on the back and edge of the silicon wafer, and depositing a SiN<X> mask; carrying out P diffusion on the back of the silicon wafer, performing plasma etching on the self-diffusion layer on the edge, and carrying out washing by employing corrosive liquid to remove the SiN<X> mask and a phosphorosilicate glass layer on the surface; using an ALD method to form a Al<2>O<3> passive film on the front surface of the silicon wafer, depositing a SiN<X> protection film on the front surface of the silicon wafer and depositing SiN<X> antireflective film on the back of the silicon wafer; and carrying out silk-screen printing to form an electrode for sintering.

Description

technical field [0001] The invention relates to the field of photovoltaic equipment manufacturing, in particular to a method for preparing an N-type single-crystal double-sided battery. Background technique [0002] In the current photovoltaic market, P-type polycrystalline cells are commonly used, but the photovoltaic conversion efficiency of this P-type polycrystalline cell is not high. With the advancement of technology, the production cost of N-type silicon wafers is also further reduced. In addition, because the efficiency of monocrystalline materials is higher than that of polycrystalline materials, N-type solar cells have also been used more and more. Moreover, now There is a double-sided diffusion method for N-type single-crystal double-sided cells in the technology. First, boron is diffused after texturizing the front side of the silicon wafer, and then silicon nitride and silicon oxide are deposited by CVD as a mask for the back side. Phosphorus is an effective ba...

AI Technical Summary

Problems solved by technology

However, the existing technology is to mechanically engrave small pyramids on the front of the silicon wafer, and put the engraved silicon wafer into the corrosive solution to make texture. The hidden damage formed by mechanical engraving is under the uncontrollable erosion of the corrosive solution. It is easy to cause the fragmentation rate of silicon wafers to increase, which needs to be improved urgently