Patent ID: 7354778

Claim:
A method for determining an end point of a plasma etching process using ionized process gases for cleaning etching of a processing chamber that is used for coating or etching processes during the manufacture of semiconductor components, comprising the steps of: monitoring a DC bias voltage profile of a plasma generator during a cleaning etching process run, wherein the DC bias voltage is the voltage measured between ground and a decoupling electrode of the plasma generator disposed within the processing chamber, and wherein the voltage measurement points are selected so that the measured voltage profile has a maximum in the voltage profile at the endpoint of the cleaning etching process indicating that the processing chamber is clean; comparing the DC bias voltage to a stored value representing a clean processing chamber, wherein the stored value is predetermined from a prior plasma cleaning etching process run; and terminating the plasma cleaning etching process by disconnecting a supply of process gases and deactivating the plasma generator when said DC bias voltage reaches said predetermined value.