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:
Jun. 16, 2015
Filed:
Mar. 14, 2013
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Costel Biloiu, Rockport, MA (US);
Alexander Soskov, Danvers, MA (US);
Chris Leavitt, Gloucester, MA (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
A hardware interlock system for monitoring operation of RF plasma sources. The hardware interlock system includes an RF generator operative to transmit a forward RF power used to generate plasma in a plasma chamber. A derivative based hardware interlock circuit is coupled in series with the RF generator. The derivative based hardware interlock circuit determines a reflected RF power derivative value indicative of the speed of change in reflected RF power values in the RF plasma ion source. An analog/digital (A/D) logic circuit is coupled with the derivative based hardware interlock circuit. The A/D logic circuit can shut down the RF generator output when the reflected RF power derivative value exceeds a threshold.