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. 14, 2019
Filed:
Sep. 24, 2014
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Bon-Woong Koo, Andover, MA (US);
Richard M. White, Newmarket, NH (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
A plasma processing apparatus includes a process chamber housing defining a process chamber, a platen positioned in the process chamber for supporting a workpiece, a source configured to generate plasma in the process chamber, and a biasing system. The biasing system is configured to bias the platen with a negatively biased DC signal to attract ions from the plasma towards the workpiece during a first processing time interval and configured to bias the platen with a positively biased DC signal to repel ions from the platen towards interior surfaces of the process chamber housing during a cleaning time interval. The cleaning time interval is separate from the first processing time interval and occurs after the first processing time interval.