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. 12, 2021
Filed:
Jun. 28, 2019
Toshiba Memory Corporation, Minato-ku, JP;
TOSHIBA MEMORY CORPORATION, Minato-ku, JP;
Abstract
A semiconductor memory device of an embodiment includes a stacked body having a stepped portion in which a plurality of metal layers is stacked via an insulating layer, and end portions of the plurality of metal layers are formed in a stepwise manner, a plurality of columnar portions arranged in steps of the stepped portion and penetrating the stepped portion, and a band portion provided near a leading end portion of the metal layer of a lowermost step of the stepped portion, the band portion extending in a first direction along the leading end portion and dividing the stacked body and a peripheral region of the stacked body, in which a coverage of the columnar portions arranged in the lowermost step is larger than a coverage of the columnar portions arranged in an upper step adjacent to the lowermost step only in a second direction toward a region where memory cells are arranged.