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:
Mar. 17, 2015
Filed:
Jan. 27, 2014
Ngk Insulators, Ltd., Aichi, JP;
Yasunori Iwasaki, Kitanagoya, JP;
Akiyoshi Ide, Kasugai, JP;
Yuji Hori, Owariasahi, JP;
Tomoyoshi Tai, Inazawa, JP;
Sugio Miyazawa, Kasugai, JP;
NGK Insulators, Ltd., Aichi, JP;
Abstract
A composite waferincludes a supporting substrateand a semiconductor substratewhich are bonded to each other by direct bonding. The supporting substrateis a translucent alumina substrate with an alumina purity of 99% or more. The linear transmittance of the supporting substrateat the visible light range is 40% or less. Furthermore, the total light transmittance from the front at a wavelength of 200 to 250 nm of the supporting substrateis 60% or more. The average crystal grain size of the supporting substrateis 10 to 35 μm. The semiconductor substrateis a single crystal silicon substrate. Such a composite waferhas insulation performance and thermal conduction comparable to those of a SOS wafer, can be manufactured at low cost, and can be easily made to have a large diameter.