Patent ID: 8759162
Filing Date: 2014-06-24
Classification: H01L

Abstract:
1. A method of manufacturing a nonvolatile semiconductor memory device, the nonvolatile semiconductor memory device including a plurality of memory strings each having a plurality of electrically rewritable memory cells connected in series, comprising: depositing a plurality of first conductive layers on a substrate; penetrating the plurality of first conductive layers to form a penetration hole; forming a charge storage layer on a side surface of the penetration hole; forming a semiconductor layer so as to fill the penetration hole; forming a stepped portion formed in a stepped shape in the plurality of first conductive layers such that positions of ends of the plurality of first conductive layers differ from one another; and forming a plurality of second conductive layers extending upwardly from an upper surface of the first conductive layers configuring the stepped portion, the plurality of second conductive layers being formed such that upper ends thereof are aligned with a surface parallel to the substrate, and such that a diameter thereof decreases from the upper end thereof to a lower end thereof, and being formed such that the greater a length thereof in the perpendicular direction, the larger a diameter of the upper end thereof.