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:
May. 14, 2002
Filed:
Oct. 28, 1999
Applicant:
Inventors:
Izumi Fusegawa, Nishigo-mura, JP;
Masakazu Sato, Nishigo-mura, JP;
Assignee:
Shin-Etsu Handotai Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B32B 3/02 ; C30B 1/500 ;
U.S. Cl.
CPC ...
B32B 3/02 ; C30B 1/500 ;
Abstract
The high quality silicon wafer of large diameter is invented by mainly paying attention to the particles ascribed to the crystal and the wafer is optimal for manufacturing ultra highly integrated devices. The silicon wafer is of diameter of 300 mm and larger sliced from a single-crystal silicon ingot pulled by CZ method, the surface is mirror-polished and cleaned with ammonia based cleaning solution, and the number of particles of 0.083 &mgr;m and larger in size detected on its main surface is 120 and smaller and/or particles of 0.090 &mgr;m and larger in size is smaller than 80.