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. 09, 2010
Filed:
Nov. 28, 2007
Kenji Aoki, Tokyo, JP;
Toru Yamazaki, Tokyo, JP;
Takehiro Watanabe, Tokyo, JP;
Naoyuki Hamada, Tokyo, JP;
Kenji Aoki, Tokyo, JP;
Toru Yamazaki, Tokyo, JP;
Takehiro Watanabe, Tokyo, JP;
Naoyuki Hamada, Tokyo, JP;
NIHON Micro Coating Co., Ltd., Tokyo, JP;
Abstract
A hard crystal substrate such as a GaN substrate or a SiC substrate is polished by using polishing oil slurry having abrading particles of artificial diamond clusters dispersed in a dispersant. The artificial diamond clusters include approximately spherical agglomerate particles with average particle size D50 of 20 nm or more and 50 nm or less, having primary particles with particle diameters of 2 nm or more and 10 nm or less. A rough polishing process is carried out first such that an average surface roughness of 0.5 nm or more and 1 nm or less is obtained, followed by a finishing process such that the average surface roughness of said surface becomes 0.2 nm or less.