Patent ID: 9537037
Date: 2017-01-03
CPC Classifications: H01L,Y02E,Y02P

Claim:
1. A wet etching method for an N-type bifacial cell, comprising: (1) providing an N-type silicon wafer, proceeding with surface structuralization on the N-type silicon wafer, and producing a PN junction on a surface of the N-type silicon wafer by using a boron diffusion technique; (2) proceeding with a first mixed acid washing, etching the PN junction on an edge and a back surface of the N-type silicon wafer; (3) proceeding with a first pure water washing and a first alkaline washing, removing residual acid solution from the surface of the N-type silicon wafer; (4) proceeding with a second pure water washing and a second mixed acid washing, removing residual impurities from the surface of the N-type silicon wafer; (5) proceeding with a third pure water washing and air drying; and (6) after air drying, completing etching on the N-type bifacial cell.