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:
Dec. 21, 2021
Filed:
Jan. 24, 2020
Shin-etsu Handotai Co., Ltd., Tokyo, JP;
Yasushi Mizusawa, Annaka, JP;
SHIN-ETSU HANDOTAI CO., LTD., Tokyo, JP;
Abstract
An evaluation method of a silicon epitaxial wafer, including using a photoluminescence (PL) measuring apparatus to measure a PL spectrum of the mirror wafer and adjusting the apparatus so emission intensity of a TO-line becomes 30000 to 50000 counts, irradiating the silicon epitaxial wafer with an electron beam, measuring PL spectrum from an electron beam irradiation region, and sorting out and accepting a silicon epitaxial wafer which has emission intensity resulting from a CCdefect of the PL spectrum being 0.83% or less of the emission intensity of the TO-line and from a COdefect being 6.5% or less of the emission intensity of the TO-line.