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:
Feb. 15, 1994
Filed:
Jul. 31, 1991
Applicant:
Inventors:
Assignee:
Toshiba Ceramics Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01J / ; G01N / ;
U.S. Cl.
CPC ...
356364 ; 356370 ; 356351 ; 356432 ; 356433 ; 250225 ;
Abstract
The invention related to a method for determining a silicon wafer in which the interstitial oxygen concentration of a pulled silicon wafer is calculated on the basis of a light transmission characteristic measured by utilizing parallel polarized light incident at the brewster angle into the pulled silicon wafer and a further light transmission characteristic measured by utilizing parallel polarized light incident at the brewster angle into the floating zone silicon wafer function as a reference silicon wafer. The interstitial oxygen concentration value of the pulled silicon wafer is compared with a reference value to determine a defect in pulled silicon wafer.