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:
Oct. 27, 2009
Filed:
Sep. 07, 2004
Isao Yokokawa, Gunma, JP;
Kiyoshi Mitani, Gunma, JP;
Isao Yokokawa, Gunma, JP;
Kiyoshi Mitani, Gunma, JP;
Shin-Etsu Handotai Co., Ltd., Tokyo, JP;
Abstract
Disclosed is a method for cleaning a multilayer substrate at least having a silicon single crystal wafer with a SiGe layer epitaxially grown on a surface of the silicon single crystal wafer, where the SiGe layer is an outermost surface of the SiGe layer and then cleaning the multilayer substrate with a first cleaning liquid capable of etching the protective film so that the protective film remains. The protective film prevents roughening of the surface of the SiGe layer while the cleaning is performed. The cleaning is performed. The cleaning is performed so that a thickness of the remaining protective film is from 1 nm to 100 nm.