The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 10, 1998
Filed:
Oct. 30, 1995
Edward Ross Castro, San Jose, CA (US);
Ken Edwin Tokunaga, Fremont, CA (US);
Boris V Atlas, San Jose, CA (US);
David Ru-Chen Liu, Saratoga, CA (US);
Lam Research Corporation, Fremont, CA (US);
Abstract
A bipolar electrostatic chuck system having a bipolar electrostatic chuck for securely holding a wafer on the surface of the bipolar electrostatic chuck. The bipolar electrostatic chuck system includes a negative-offset power supply for providing a positive potential level and a negative potential level. The positive potential level is positively biased relative to a common reference voltage level by a first magnitude while the negative potential level is negatively biased relative to the same common reference voltage level by a second magnitude, which is larger than the first magnitude. Further, the bipolar electrostatic chuck includes a positive pole, which is coupled to the negative-offset power supply for biasing the positive pole at the positive potential level when the negative-offset power supply is turned on. Additionally, the bipolar electrostatic chuck includes a negative pole, which is coupled to the negative-offset power supply for biasing the negative pole at the negative potential level when the negative-offset power supply is turned on.