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:
Nov. 23, 1999
Filed:
Dec. 29, 1997
Hisami Motoura, Kanagawa, JP;
Eiichi Asano, Kanagawa, JP;
Komatsu Electronic Metals Co., Ltd., Kanagawa, JP;
Abstract
The evaluating method includes: dipping a mirror-polished silicon wafer in a dilute hydrofluoric acid; washing the surface of the silicon wafer; subjecting the surface-washed silicon wafer to a heat treatment in an oxygen atmosphere to form a thermal oxidation film; forming a predetermined number of polycrystalline silicon electrodes having a predetermined area on the thermal oxidation film; applying a voltage to each electrode between the predetermined number of polycrystalline silicon electrodes and the silicon wafer; and judging the quality of the mirror-polishing process of the silicon wafers in accordance with the breakdown electric field intensity of the leakage current obtained by measuring the oxide film insulation.