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. 16, 1991
Filed:
May. 05, 1989
Noah Hershkowitz, Madison, WI (US);
Moo-Hyun Cho, Madison, WI (US);
Wisconsin Alumni Research Foundation, Madison, WI (US);
Abstract
A glow discharge etching apparatus includes a magnetic assembly for creating a surface magnetic field in close proximity to the walls of an etching chamber. An electrode is located within the chamber for supporting the object to the etched. A radio frequency signal is applied to the electrode so that it will emit secondary electrons upon bombardment by ions from an etching plasma created within the apparatus. A control plate may be positioned at various locations within the apparatus to regulate the amount of electron leakage to the control plate and thereby regulate the etching process. This apparatus provides improved uniformity and directionality of etching due to a low gas pressure and the surface magnetic field.