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:
Mar. 04, 2008
Filed:
Dec. 03, 2004
Sakae Koyata, Tokyo, JP;
Tadashi Denda, Tokyo, JP;
Masashi Norimoto, Tokyo, JP;
Kazushige Takaishi, Tokyo, JP;
Sakae Koyata, Tokyo, JP;
Tadashi Denda, Tokyo, JP;
Masashi Norimoto, Tokyo, JP;
Kazushige Takaishi, Tokyo, JP;
SUMCO Corporation, Tokyo, JP;
Abstract
A surface of a semiconductor wafer which has been lapped is ground. This removes a damage caused on the wafer surface during lapping, thereby increasing the flatness of the wafer surface. Next, the wafer is subjected to composite etching and the both surfaces are polished, i.e., subjected to mirror polishing while the wafer rear surface is slightly polished so as to obtain a single-side mirror surface wafer having a difference between the front and the rear surfaces. As compared to mere acid etching or alkali etching, it is possible to manufacture a single-side mirror surface wafer having a higher flatness.