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:
Dec. 29, 1992
Filed:
Jan. 11, 1991
Jun-ichi Nishizawa, Sendai, JP;
Tadahiro Ohmi, Sendai, JP;
Zaidan Hojin Handotai Kenkyu Shinkokai, Sendai, JP;
Abstract
A semiconductor thyristor of the Static Induction type having a split-gate structure, e.g., driving gates and non-driving gates, for controlling cathode-anode current flow. The split-gate structure comprises a plurality of primary driving gates formed in recesses of the channel region which respond to an external control signal for providing primary current control, and a plurality of secondary non-driving gates which are influenced by electric fields in the channel region extant during thyristor operation for providing secondary current control. In operation, the driving and non-driving gates coact so that the non-driving gates, having an induced potential lower than the potential applied to the driving gates, absorb charge carriers injected in the channel during thyristor operation. The relative disposition of the non-driving gates and the anode, as well as the respective doping concentrations of the anode and channel regions, enable the non-driving gates to absorb a substantial portion of charge carriers injected from the anode into the channel during high-power operation. Fast turn-on and turn-off is achieved by exclusion of the non-driving gate capacitance in the driving gate circuit.