公开(公告)号：US09812334B2

公开(公告)日：2017-11-07

申请号：US14436037

申请日：2013-12-31

Applicant: CSMC TECHNOLOGIES FAB1 CO., LTD.

Inventor： Qiliang Sun

IPC: H01L21/311 ,  B81C1/00

CPC classification number: H01L21/31116 ,  B81C1/00476 ,  B81C2201/0132

Abstract: A corrosion method of a passivation layer (320) of a silicon wafer (300) includes: pouring hydrofluoric acid solution (100) into a container (200) with an open top; putting the silicon wafer (300) to the opening of the container (200) and one side of the silicon wafer (300) with the passivation layer (320) is opposite to the hydrofluoric acid solution (100); the hydrogen fluoride gas generated from the volatilization of the hydrofluoric acid solution (100) corrodes the passivation layer (320) of the silicon wafer (300), the corrosion time is larger or equal to (thickness of the passivation layer/corrosion rate). By means of the corrosion of the passivation layer of silicon wafer by the fluoride gas generated from the volatilization of the hydrofluoric acid solution, the fluoride gas can fully touch the passivation layer; therefore the passivation layer can be completely corroded, and the corrosion precision is high.