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. 01, 1992
Filed:
Mar. 29, 1990
Yasuo Ashizawa, Kawasaki, JP;
Takao Noda, Yokohama, JP;
Mitsuhiro Kushibe, Tokyo, JP;
Masahisa Funemizu, Tokyo, JP;
Kazuhiro Eguchi, Yokohama, JP;
Yasuo Ohba, Yokohama, JP;
Yoshihiro Kokubun, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A p-type GaAs or AlGaAs thin film is formed by a MOCVD method. In the growing step of the thin film, the thin film is doped with a high concentration of carbon atoms forming an acceptor level such that the carrier concentration of the thin film falls within the range of between 1.times.10.sup.18 cm.sup.-3 and 1.times.10.sup.20 cm.sup.-3. At least one of trimethyl gallium and trimethyl aluminum is used as a raw material gaseous compound of III-group element, and arsine is used as a raw material gaseous compound of V-group element. The thin film is formed by an epitaxial growth under the molar ratio V/III of the V-group element supply rate to the III-group element supply rate, which is set at such a small value as 0.3 to 2.5, the temperature of 450 to 700.degree. and the pressure of 1 to 400 Torr. The thin film formed under these conditions exhibits a mirror-like smooth surface, and the film-growth rate is dependent on the supply rate of the V-group element.