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:
Nov. 15, 2011
Filed:
Nov. 10, 2005
Applicants:
Tsuyoshi Moriya, Nirasaki, JP;
Kouji Mitsuhashi, Nirasaki, JP;
Akira Uedono, Tsukuba, JP;
Inventors:
Assignee:
Tokyo Electron Limited, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/26 (2006.01);
U.S. Cl.
CPC ...
Abstract
A focus ring is shaped by cutting off a silicon carbide body formed by a sintering method or a CVD method. The shaped focus ring is exposed to a plasma generated from at least one of a carbon tetra fluoride gas and an oxygen gas for producing impurities, and the impurities are introduced to void-like defects existing in the vicinity of a surface of the focus ring. Subsequently, positrons are injected in the vicinity of the surface of the focus ring into which the impurities are introduced, and the defect density in the vicinity of the surface of the focus ring is detected by the positron annihilation method.