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:
Jan. 13, 2015
Filed:
May. 06, 2011
Aseem K. Srivastava, Andover, MA (US);
William F. Divergilio, Cambridge, MA (US);
Aseem K. Srivastava, Andover, MA (US);
William F. DiVergilio, Cambridge, MA (US);
Axcelis Technologies, Inc., Beverly, MA (US);
Abstract
The present disclosure is directed towards a method and apparatus for generating an abatement plasma downstream of a processing chamber using an RF plasma ignited and sustained with an integrated power oscillator circuit driven by feedback based upon a load of the abatement plasma. In one embodiment, a plasma ashing system includes an abatement system configured to receive an effluent byproduct from an upstream processing chamber containing a workpiece. The effluent byproduct is provided along an exhaust conduit to a downstream afterburner unit having an integrated power oscillator, that relies upon an oscillating circuit operatively coupled to an antenna to ignite the abatement plasma within the exhaust conduit. The antenna, together with the plasma load, form a resonant tank circuit, which provides a feedback that drives operation of the oscillating circuit, thereby allowing the oscillating circuit to vary its output based upon changes in the abatement plasma load.