Patent ID: 6628500
Filing Date: 2003-09-30
Classification: H01L

Abstract:
A method of dechucking, from an electrostatic chuck incorporating two electrodes, a substrate held by one or more residual forces to the chuck, the dechucking method comprising the steps of:(a) reducing a residual chucking force due to the electrostatic chuck polarisation by the application of a first voltage to said two electrodes, the magnitude of the first voltage being determined by ramping the voltage down whilst measuring the extent to which the substrate is held to the chuck; (b) holding a preferred magnitude of the first voltage for a minimum residual chucking force for a desired period; (c) as a subsequent step, contacting the chuck with the substrate attached thereto with a plasma for a time sufficient substantially to remove any residual charge from the surface of the substrate and the chuck; and (d) subsequently to, or simultaneously with, step (c) removing the substrate from the chuck.