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:
Jan. 17, 1989
Filed:
Jul. 27, 1981
Satoshi Hiyamizu, Tokoyo, JP;
Toshio Fujii, Kanagawa, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A high electron mobility single heterojunction semiconductor devices having a layer configuration comprising a N-type AlGaAs layer grown on an undoped GaAs layer grown on an undoped AlGaAs layer grown on a semiconductor substrate containing an impurity producing a deep level. The undoped AlGaAs layer has at least three functions including (a) a getter for the deep level impurity which may be diffused from the substrate during an annealing process, (b) a buffer improving the crystal condition of the undoped GaAs layer, and (c) a test layer grown for the purpose of predetermining the intensity of molecular or ion beams for each of Al, Ga, As and dopants e.g. Si. This allows annealing processes and ion implantation processes to be introduced to the method for production of this type of semiconductor devices without reducing the electron mobility thereof.