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:
Mar. 12, 2002
Filed:
Dec. 16, 1999
Ryo Hattori, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
In a field effect transistor such as high output FET or low noise HEMT, a layer for facilitating re-combination of carriers (for example a superlattice buffer layer), an undoped compound semiconductor layer having a higher resistance than a channel layer and the channel layer made of a compound semiconductor are layered successively. In the layer for facilitating re-combination of carriers, for example, oxygen of high concentration is introduced, to facilitate the non-radiative recombination which shortens the life of injected carriers. The layer for facilitating re-combination of carriers is also formed by forming the superlattice layer at a lower temperature than the channel layer. Thus, efficiency and voltageproofness on high frequency, high output power operation is improved further, and noises can be decreased further on high frequency, low noise operation.