Patent ID: 6660528
Filing Date: 2003-12-09
Classification: G01N,Y10T

Abstract:
A method for determining the number of contaminating particles in a process chamber comprising the steps of:providing a process chamber equipped with a gas inlet; conducting a chemical process on a substrate that generates contaminating particles in said chamber, evacuating a process gas from said chamber to a pressure of not higher than 1 mTorr; flowing at least one process gas used in said chemical process into said chamber at a flow rate of at least 30 sccm; evacuating said at least one process gas from said chamber to a pressure of not higher than 1 mTorr; flowing at least one process gas used in said chemical process into said chamber at a flow rate of at least 30 sccm; evacuating said at least one process gas from said chamber to a pressure of not higher than 1 mTorr; and counting number of particles that have fallen onto a top surface of said substrate.