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:
Oct. 04, 2011
Filed:
Jan. 07, 2009
Aki Takahashi, Ota-Ku, JP;
Masaaki Nagashima, Ota-Ku, JP;
Aki Takahashi, Ota-Ku, JP;
Masaaki Nagashima, Ota-Ku, JP;
Disco Corporation, Tokyo, JP;
Abstract
In a wafer processing method, rough grinding using a first grinding stone is divided into first and second steps. In the first step, a wafer is processed into a concave shape at a first transfer rate with a reinforcing rib area slightly left. Thereafter, as primary rough grinding in the second step, the grinding stone is positioned slightly on the inner circumferential side and the wafer is further processed into the concave portion at a second transfer rate faster than the first transfer rate. Since the first transfer rate is suppressed to a rate not to cause a burst chipping, a burst chipping resulting from the second step fast in the processing rate to ensure productivity will occur at the stepped edge portion on the inside of the reinforcing rib area surface. Thus, the flatness of the reinforcing rib area can be ensured.