Patent ID: 6185085
Filing Date: 2001-02-06
Classification: H01L

Abstract:
A unipolar electrostatic chuck for holding a semiconductor wafer or the like, comprising:a first electrically conductive member having a wafer-attracting surface extending parallel to and essentially coextensive with said wafer;a second electrically conductive member surrounding said first member and having a wafer-engaging edge extending beyond said wafer-attracting surface, said wafer-engaging edge engaging the outer periphery of said wafer and holding said wafer in spaced relationship to said wafer-attracting surface so as to form a gap therebetween;a layer of electrically insulating material between said first and second members;an outer housing surrounding said first conductive member and formed of an electrically insulating material, said housing including an outer edge extending beyond said wafer engaging edge and contacting the sides of said wafer to hold said wafer against lateral movement when said wafer is in engagement with said wafer engaging surface; and,an electrical power supply having first and second terminals of opposite polarity respectively connected to said first and second conductive members.