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. 19, 2010
Filed:
Jul. 07, 2008
Applicants:
Keiichi Kajiyama, Ota-Ku, JP;
Kazuhisa Arai, Ota-ku, JP;
Inventors:
Keiichi Kajiyama, Ota-Ku, JP;
Kazuhisa Arai, Ota-ku, JP;
Assignee:
Disco Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 21/44 (2006.01);
U.S. Cl.
CPC ...
Abstract
A wafer processing method having a step of reducing the thickness of a wafer in only a device forming area where semiconductor chips are formed by grinding and etching the back side of the wafer to thereby form a recess on the back side of the wafer. At the same time, an annular projection is formed around the recess to thereby ensure the rigidity of the wafer. Accordingly, handling in shifting the wafer from the back side recess forming step to a subsequent step of forming a back side rewiring layer can be performed safely and easily.