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:
May. 03, 2005
Filed:
Feb. 20, 2004
Tetsuo Ono, Iruma, JP;
Katsumi Setoguchi, Ome, JP;
Hideyuki Yamamoto, Kudamatsu, JP;
Hitachi High-Technologies Corporation, Tokyo, JP;
Abstract
A plasma processing method of processing a substrate by controlling the application of a bias to the substrate independently of generation of plasma. The method includes modulating periodically an output value of a high-frequency voltage applied to a substrate base and changing a duty ratio of the periodic modulation for one of each processed substrate and for each of a plurality of processed substrates. The duty ratio is defined as a ratio of a sub-period of a period of the period modulation, during which a large voltage of the output value of the high-frequency voltage is applied, to the period of the periodic modulation.