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. 10, 2001
Filed:
Mar. 15, 2000
Stephen Wells, West Sussex, GB;
Applied Materials, Inc., Santa Clara, CA (US);
Abstract
In a power control apparatus for controlling power supply of an ion source having an indirectly headed cathode, the cathode bias power supply which provides a bias potential between the filament and cathode has an output that is effected by changes in impedance of the electron flow in the region between the filament and the cathode. Such impedance changes can arise due to changes in the chemistry of materials in this region, changes in gas pressure or physical changes, for example. A bias supply controller in the power control apparatus maintains the output power of the cathode bias power supply unit at a desired level, thus not effected by changes in impedance of the electron flow between the filament and the indirectly heated cathode.