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:
Jul. 24, 2001
Filed:
Mar. 31, 1999
Arthur M. Howald, Pleasanton, CA (US);
John P. Holland, San Jose, CA (US);
Christopher Olson, Eldorado, CA (US);
Lam Research Corporation, Fremont, CA (US);
Abstract
A tendency for a discontinuity to occur in the amount of power reflected back to an r.f. bias source of a vacuum plasma processor is overcome by controlling the r.f. bias source output power so the power delivered to plasma in a vacuum processing chamber remains substantially constant. The r.f bias source output power is changed much faster than changes in capacitors of a matching network connecting the r.f. bias power source to an electrode of a workpiece holder processor. A capacitive impedance component of the plasma is determined by optically measuring the thickness of a plasma sheath in the chamber.