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. 21, 1995
Filed:
Jun. 07, 1993
Applicant:
Inventors:
Shinichiro Takatani, Koganei, JP;
Takeshi Kikawa, Kokubunji, JP;
Chushirou Kusano, Tokorozawa, JP;
Masatoshi Nakazawa, Koganei, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B44C / ;
U.S. Cl.
CPC ...
156628 ; 156635 ; 156662 ;
Abstract
A compound semiconductor is etched by a step of substituting a composite element of a compound semiconductor with other element, thereby forming a compound layer on the surface of the compound semiconductor and a step of removing the compound layer from the surface. Etching depth is controlled not by etching time, but by the number of runs (repetitions) of the etching step, and thus can be precisely controlled.