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:
Feb. 06, 1996
Filed:
Apr. 05, 1995
Hidetoshi Nakanishi, Kawasaki, JP;
Yasunori Usui, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A P type source region is formed in a grid mesh-like pattern in one major surface portion of an N.sup.- type semiconductor substrate. A P type base region and P.sup.- type base region are each formed in the one major surface portion of the N.sup.- type semiconductor substrate at an area between those grid mesh-like portions of the P type source region. An N type emitter region is formed in the P type base region. An N type emitter region is formed in the P.sup.- type base region. A gate electrode is formed over the P type source region, N.sup.- type semiconductor substrate, P type base region and P.sup.- type base region. The gate electrode is formed in a grid mesh-like pattern as viewed from above the N.sup.- type semiconductor substrate. A cathode electrode is contacted with the P type source region, P.sup.- type base region and N type emitter regions. A P.sup.+ type emitter layer is formed on an other major surface side of the N.sup.- type semiconductor substrate. An N.sup.+ type buffer layer is formed between the N.sup.- type semiconductor substrate and the P.sup.+ type emitter layer. An anode electrode is contacted with the P.sup.+ type emitter layer. A cell acts as a switch at a turn-on time and a resultant MCT is rapidly turned on. Those cells .alpha. and .beta. have such an arrangement as to improve the turn-off characteristic.