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:
Sep. 04, 2018
Filed:
May. 12, 2017
Disco Corporation, Tokyo, JP;
Disco Corporation, Tokyo, JP;
Abstract
A gettering property evaluating method for a wafer includes: a gettering layer forming step of polishing a back surface opposite to a front surface of a semiconductor wafer by use of a polishing wheel to form polishing marks on the back surface and to form a gettering layer inside the semiconductor wafer and beneath the polishing marks; an imaging step of imaging at least a unit region of the back surface formed with the polishing marks by imaging means; a counting step of counting the number of the polishing marks having a width of 10 to 500 nm present in the unit region imaged; and a comparing step of comparing the number of the polishing marks counted by the counting step with a predetermined value to determine whether or not the counted number is not less than the predetermined value.