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:
Feb. 09, 1999
Filed:
Apr. 23, 1997
Roger Patrick, Mountain View, CA (US);
Phillip Jones, Fremont, CA (US);
LAM Research Corporation, Fremont, CA (US);
Abstract
A charge monitoring apparatus measures an electrical charge deposited on a multiple-layered workpiece, such as a semiconductor wafer, in a plasma processing system. The apparatus includes a charge collection electrode (CCE), a non-conducting patterned layer and a voltage or current sensor. The patterned layer is provided on the CCE and includes a plurality of openings that extend through the patterned layer to the conducting surface of the CCE. The openings create a topology having an adequate aspect ratio to cause electron shading to occur during plasma processing of the workpiece. The voltage or current sensor includes an EEPROM transistor that stores information regarding the amount of electrical charge that accumulates on the CCE during plasma processing.