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. 13, 1993
Filed:
Sep. 11, 1991
Nihon Shinku Gijutsu Kabushiki Kaisha, Chigasaki, JP;
Abstract
A plasma ashing apparatus has a vacuum treatment chamber for receiving therein a substrate coated with a resist film, a reactive gas introduction pipe equipped with a plasma applicator, a vacuum exhaust pipe, a heating means for heating the substrate, and two pieces of electrodes disposed in parallel to each other. One of the electrodes is a substrate electrode and the other thereof is a circular counter electrode. These two electrodes are commonly connected to an RF power source to thereby constitute a cathode electrode. Multiple concentric perforations are formed in the counter electrode except for a rib portion. A central perforation is formed in the center of the counter electrode. The concentric perforations are formed at every distance, from the center, equivalent to a diameter of the central perforation, while leaving circular electrode surfaces corresponding in width to a radius of of the perforation.