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. 13, 1998
Filed:
Aug. 28, 1996
Hidetoshi Furukawa, Osaka, JP;
Daisuke Ueda, Osaka, JP;
Matsushita Electronics Corporation, Osaka, JP;
Abstract
Variations in the waveform of high-frequency signals amplified by a field-effect transistor (FET) in a power amplification circuit due to changes in temperature are reduced. A FET having an n-type active layer, a source electrode, a drain electrode and a gate electrode is formed on a (1 0 0)-crystal plane of a semi-insulating GaAs substrate. The FET is protected by a passivation film. The angle .theta., formed between the longitudinal axial direction of the gate electrode and the <0 -1 -1>-direction, is set at an angle of from 0.degree. to 90.degree. corresponding to the impurity concentration of the n-type active layer, in order that the temperature coefficient of the FET threshold voltage becomes substantially equal to the temperature coefficient of the gate bias voltage applied from a power supply to the gate electrode. If the angle .theta. is set at 45.degree., then the temperature coefficient of the FET threshold voltage becomes zero.