Process for fabricating semiconductor wafers with external gettering

摘要

A method of fabricating a semiconductor wafer is disclosed. The method reduces the number of processing steps and produces a low cost semiconductor wafer having external gettering. The method includes slicing the wafer from a single silicon crystal ingot and etching the wafer to clean impurities and residue from slicing. Thereafter, the wafer is double side polished which creates damage on both the front and back surfaces. The damage on the front surface is then removed in a subsequent plasma assisted chemical etching step and touch polishing operation which significantly improves the flatness of the wafer. The damage on the back surface created by the double side polishing remains and getters defects from the front surface and bulk regions of the wafer.