Patent ID: 8617411
Filing Date: 2013-12-31
Classification: H01J,H01L

Abstract:
1. A method for etching a layer on a substrate in a semiconductor processing chamber, said chamber having a plasma generating region and a substrate processing region, said plasma generating region being separated from said substrate processing region by a separating plate structure, comprising: introducing a first gas into said substrate processing region of said chamber, said first gas being an etchant gas suitable for etching said layer; introducing an inert gas into said plasma generating region such that a pressure of said inert gas in said plasma generating region is greater than a pressure of said etchant gas in said substrate processing region; allowing said first gas to be present in said substrate processing region of said chamber for a period of time sufficient to cause adsorption of at least some of said first gas into said layer; replacing at least 80% of said first gas in said chamber with said inert gas after said period of time expires; generating metastables from said inert gas; and etching said layer with said metastables.