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:
May. 13, 2003
Filed:
Dec. 12, 2001
Applicant:
Inventor:
Fumihiko Hirose, Yokohama, JP;
Assignee:
Mitsubishi Heavy Industries, Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/100 ;
U.S. Cl.
CPC ...
H01L 2/100 ;
Abstract
The surface cleaning method of semiconductor substrate comprises, the steps of, immersing a substrate of a first conductive type having Ge or SiGe mixing Ge and Si at least in the surface layer in a solution of hydrofluoric acid, and removing foreign matters from the surface of the substrate without overetching the surface of the substrate, pouring pure water on the substrate to wash away the solution of hydrofluoric acid applied at the step (a) from the surface of the substrate, and immersing the substrate in a solution of hydrogen peroxide, and removing foreign matters from the surface of the substrate without overetching the surface of the substrate.