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. 21, 2002
Filed:
Nov. 17, 2000
Kazuhiko Onda, Tokyo, JP;
Nec Corporation, Tokyo, JP;
Abstract
There is disclosed a field effect transistor having a two-stage recess structure formed upon an InP substrate and showing stable device characteristics and a low contact resistance. The FET is manufactured as follows. Upon an InP substrate a channel layer electron supply layers and an undoped InAlAs Schottky layer an n-type InAlAs first cap layer and an n-type InGaAs second cap layer are formed in succession, following which a second recess opening is formed by etching from the surface of the second cap layer to just the surface of said Schottky layer or further to a level to remove a part of the Schottky layer. A first recess opening is formed by side-etching the second cap layer using an etchant of which etching selectively of InGaAs over InAlAs is 30 or more.