DETECTING THE ENDPOINT OF A CLEANING PROCESS

摘要

A method for detecting the endpoint of a plasma cleaning process which involves the use of BCl and similar plasmas is provided. A method for monitoring and measuring the endpoint of a cleaning process comprises: providing a surface, which comprises a metal that can react with a cleaning agent and which has residues comprising a metallic material that can react with a plasma cleaning agent at a reaction rate slower than that between the metal and cleaning agent; removing the residues from the surface by contacting the residues with the cleaning agent for a predetermined time sufficient to volatilize the residues and form a volatilized residue product which is separated from the surface according to the formation of the product; maintaining the cleaning agent in contact with the residues until the cleaning agent comes into contact with the surface by removing the residues and reacts with metal of the surface to volatilize the metal thereof; monitoring each amount of the volatilized metal and the cleaning agent to measure the endpoint of the cleaning process; and finishing the cleaning process at a time when the ratio of the amount of the volatilized metal to the amount of cleaning agent increases from a lower value to a higher value.