Patent ID: 8530359
Filing Date: 2013-09-10
Classification: C23F,C25F,H01L

Abstract:
1. A method of removing metal from a semiconductor wafer using localized wet etching, comprising: rotating a semiconductor wafer in a wafer holder; applying a first flow pattern of wet etching solution to a first band-like impact zone of said rotating semiconductor wafer using a first etch nozzle during at least a portion of a total etching time; simultaneously applying a second flow pattern of wet etching solution to a second band-like impact zone of said rotating semiconductor wafer using a second etch nozzle during at least a portion of said total etching time, wherein said first impact zone and said second impact zone are spatially distinct from each other; and selectively controlling a first cumulative etching rate in a first local etch region of said semiconductor wafer relative to a second cumulative etching rate in a second local etch region by modulating said first flow pattern of wet etching solution.