Patent ID: 6703250
Filing Date: 2004-03-09
Classification: H01J,H01L

Abstract:
A method for automated monitoring and controlling of a semiconductor wafer plasma etching process comprising the steps of:collecting data versus time according to at least one of optical emission spectroscopy and mass spectroscopy during a plasma etching process said data representative of a concentration of at least one reactant and one product species present during the course of the plasma etching process; calculating a concentration ratio comprising the at least one reactant species and one product species at selected time intervals during the plasma etching process to create real-time concentration ratio data; retrieving model concentration ratio data determined according to a model etching process for the at least one reactant species and one product species; comparing the model concentration ratio data with the real-time concentration ratio data; and, adjusting in-situ at least one plasma process operating parameter in response to the real-time concentration ratio to approach the model reactant-product concentration ratio.