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:
Nov. 02, 1993
Filed:
Jun. 10, 1992
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor memory device having memory cells formed adjacent to each other comprises a P type semiconductor substrate having adjacent two trenches, a P.sup.+ impurity region formed in the side portions and the bottom portions of the trenches, n type first polysilicon layers serving as common electrodes formed in the upper portion of the P.sup.+ impurity region through an insulating film, second polysilicon layers formed inside and in the upper portion of the trenches formed of the first polysilicon layers through an insulating film, and a third polysilicon layer formed on the second polysilicon layers, only the third polysilicon layer constituting a connecting electrode between the adjacent memory cells.