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:
Sep. 27, 1994
Filed:
Jul. 27, 1992
Shigeo Goto, Tsukuba, JP;
Hidetoshi Matsumoto, Kodaira, JP;
Masamitsu Yazawa, Yokohama, JP;
Yasunari Umemoto, Tokorozawa, JP;
Yoko Uchida, Kawasaki, JP;
Kenji Hiruma, Tokorozawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A field-effect transistor or a bipolar transistor may be provided in which the contact resistance between a channel layer or base layer and a contact layer are reduced. For example, an InGaAs buffer layer may be formed on the substrate side of an InGaAs channel layer of a field-effect transistor and by the bypassing effect that carriers pass through this InGaAs buffer layer, the InGaAs channel layer comes in contact with the contact layer with a low resistance. The contact resistance between the InGaAs channel layer and the contact layer can be reduced to 10 ohm per a width of 10.mu.m, and as a result, the value of transconductance factor K of a field-effect transistor can be increased in 14 mA/V.sup.2 per a width of 10.mu.m.