Patent ID: 6444586
Filing Date: 2002-09-03
Classification: H01L

Abstract:
A method for removing doped silicon dioxide, said method comprising:providing a structure including: a first portion comprising doped silicon dioxide; and a second portion comprising undoped silicon dioxide; exposing said first portion and said second portion to a high density plasma etch process in a high density plasma etcher by: placing said structure within a high density plasma chamber having an upper electrode and a lower electrode; and applying a source power to said upper electrode and a bias power to said lower electrode such that a power density of less than about 1000 Watts (W) per 200 mm-diameter wafer surface is provided to said structure, said bias power being applied in a range from about 200 Watts less than said source power to about 200 Watts greater than said source power, thereby selectively removing doped silicon dioxide from said first portion at a material removal rate that is greater than the material removal rate of undoped silicon dioxide from said second portion.