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:
Jun. 02, 1992
Filed:
Jan. 22, 1991
Tomonori Ishikawa, Fujisawa, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A semiconductor device having a heterojunction and utilizing a two-dimensional electron gas formed at said the heterojunction comprises a substrate of a semi-insulating material, a first semiconductor layer of undoped indium gallium arsenide formed on the substrate, a second semiconductor layer of n-type indium aluminium arsenide formed on the first semiconductor layer and defining the heterojunction between the first semiconductor layer and the second semiconductor layer, the second semiconductor layer including an exposed region defining an exposed top surface, a third semiconductor layer of n-type gallium arsenide antimonide formed on the second semiconductor layer and having a window defined therein so as to expose the top surface of the exposed top surface region, a gate electrode formed in self-alignment with the window and in contact with the exposed top surface region of the second semiconductor layer, and ohmic electrodes formed on the cap layer in ohmic contact therewith.