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. 12, 1983
Filed:
Nov. 12, 1981
David J Harra, Santa Cruz, CA (US);
Frederick T Turner, Sunnyvale, CA (US);
Varian Associates, Inc., Palo Alto, CA (US);
Abstract
An RF etch table has a biased extension member positioned adjacent its periphery. The extension member is electrically conductive, but is insulated from other conductive members in the system. The extension member is positioned with respect to the periphery of the table in a manner such that the boundary of the plasma induced above the etch table is continued beyond the periphery of the etch table, thereby eliminating the focusing of ions onto the edges of an item being etched on the table. The potential impressed upon the extension member produces a dark space above its surface having a sufficient height so that the horizontal configuration of the sheath above the etch table is continued beyond its edges. More uniform etching is accomplished.