Patent ID: 6368678
Filing Date: 2002-04-09
Classification: C23C,H01J

Abstract:
A substrate processing system comprising:a grounded processing chamber; a substrate holder positioned in said processing chamber and electrically floating therein; a gas source coupled to said processing chamber for supplying a process gas to said processing chamber; an ion source in said chamber for ionizing said process gas to produce ions for processing a surface of a substrate disposed on said substrate holder facing said ion source, said ion source comprising an anode and an electron source; a substrate charging electron source disposed to deliver a train of electron flux pulses to a substrate supported by said substrate holder at a selected energy and time averaged current comprising a cathode duty cycle, whereby said substrate is capable of sustaining a bias to a selected negative potential with respect to ground, and a power source for biasing said anode, said electron source of said ion source and said substrate charging electron source such that said anode is biased to a positive voltage, said electron source is biased to a negative potential at said cathode duty cycle, whereby said substrate on said substrate holder is biased to a potential intermediate said electron source and said processing chamber.