SILICON WAFER PROCESSING METHOD

摘要

A silicon wafer processing method includes an etching step (13) at which an acid etching solution and an alkaline etching solution and an alkaline etching solution are placed in etching baths and a wafer having a process transformation layer and passed through a lapping step (11) and a cleaning step (12) is dipped in order in the acid etching solution and the alkaline etching solution, a surface mirror-polishing step (18) of mirror-polishing one side of the etched wafer, and a cleaning step (19) of cleaning the wafer subjected to the surface mirror polishing. The method is characterized in that at the etching step, after acid etching, alkaline etching is carried out, and the acid etching solution contains 100 wt% of acid aqueous solution mainly containing hydrofluoric acid and nitric acid and 30 wt% or more of phosphoric acid. According to this method, the planarity after the lapping is maintained, and the surface roughness can be reduced. Further, the wafer after the surface mirror polishing can have a favorable planarity and a low back surface roughness.