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. 01, 1997
Filed:
Sep. 18, 1995
Hisashi Muraoka, Yokohama, JP;
Yuji Fukazawa, Yokohama, JP;
Purex Co., Ltd., , JP;
Kabushiki Kaisha Toshiba, , JP;
Abstract
A method of examining surface defects of silicon wafer surfaces, comprising (A) preparing a semiconductor treating solution containing an impurity element labelled with a radioactive isotope; (B) bringing a silicon wafer whose crystal surface is laid bare, into contact with the treating solution to obtain a specimen wafer on which the labelled impurity has been adsorbed; (C) recording in a photostimulable phosphor layer a data of radioactivity intensible distribution present in the surface of the specimen wafer; the pattern being recorded as a latent image; and (D) reading as a visual image the data of radioactivity intensity distribution recorded in the photostimulable phosphor layer, to observe the radioactivity intensity distribution shown on the image, whereby the distribution of the surface defects being detected. It is possible to catch at a glance as a visual image the extent and distribution of the surface defects including crystal defects and surface states formed by contamination with impurities and to make easy the evaluation of silicon wafers.