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:
Dec. 05, 2006
Filed:
Nov. 24, 2004
Yoshihiro Hara, Osaka, JP;
Akira Asai, Osaka, JP;
Gaku Sugahara, Nara, JP;
Haruyuki Sorada, Osaka, JP;
Teruhito Ohnishi, Osaka, JP;
Yoshihiro Hara, Osaka, JP;
Akira Asai, Osaka, JP;
Gaku Sugahara, Nara, JP;
Haruyuki Sorada, Osaka, JP;
Teruhito Ohnishi, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
On an Si substrate, a buffer layer, a SiGe layer, and an Si cap layerare formed. A mask is formed on the substrate, and then the substrate is patterned. In this manner, a trenchis formed so as to reach the Si substrateand have the side faces of the SiGe layerexposed. Then, the surface of the trenchis subjected to heat treatment for one hour at 750° C. so that Ge contained in a surface portion of the SiGe layeris evaporated. Thus, a Ge evaporated portionhaving a lower Ge content than that of other part of the SiGe layeris formed in part of the SiGe layerexposed at part of the trench. Thereafter, the walls of the trenchare oxidized.