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. 20, 1995
Filed:
Mar. 25, 1994
Applicant:
Inventors:
Toyoaki Imaizumi, Toda, JP;
Osamu Oda, Toda, JP;
Assignee:
Japan Energy Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437105 ; 437107 ; 437126 ; 437133 ; 437174 ; 117 84 ;
Abstract
An undoped p-type GaAs epitaxial layer or an n-type GaAs epitaxial layer is grown on the surface of a wafer, and thereafter the wafer is annealed at a temperature which ranges from 800.degree. C. to 1,200.degree. C. and is equal to or higher than a predetermined critical temperature depending on the carrier concentration in the epitaxial layer before it is annealed. The epitaxial layer thus annealed is rendered semi-insulating without addition of any impurity. Accordingly, performances of an electronic device which incorporates such a wafer are improved.