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:
Aug. 03, 1999
Filed:
Nov. 20, 1995
Kohji Matsumura, Hirakata, JP;
Yasoo Harada, Hirakata, JP;
Sanyo Electric Co., Ltd., Osaka-fu, JP;
Abstract
An undoped Al.sub.0.22 Ga.sub.0.78 As spacer layer having a large forbidden bandgap and an N-Al.sub.0.22 Ga.sub.0.78 As electron-supplying layer having a large forbidden bandgap are formed in order on an undoped GaAs buffer layer having a small forbidden bandgap, and InAs quantum boxes are provided in the Al.sub.0.22 Ga.sub.0.78 As spacer layer. The size of the InAs quantum box is about 150 .ANG. and the height is about 40 .ANG.. When a predetermined drain voltage is applied, electrons are accumulated in the InAs quantum boxes from a channel formed in the vicinity of the interface with the Al.sub.0.22 Ga.sub.0.78 As spacer layer in the GaAs buffer layer. Accordingly, a drain current will not flow almost at all even if a drain voltage is applied.