Nonvolatile semiconductor memory device and operation method of the same

摘要

A nonvolatile semiconductor memory device includes a semiconductor substrate and memory transistors, each of which has a laminate formed by alternately laminating insulating films and conductive films on the semiconductor substrate, a silicon pillar going through the laminate, a tunnel insulating film arranged on the surface of the silicon pillar facing the laminate, a charge accumulating layer arranged on the surface of the tunnel insulating film facing the laminate, and a block insulating film arranged on the surface of the charge accumulating layer facing the laminate and in contact with the conductive film. During a data deletion operation, a voltage is applied on the conductive film so that the potential of the silicon pillar with respect to the conductive film decreases as the cross-sectional area of the silicon pillar decreases.

主权项

1. A nonvolatile semiconductor memory device comprising:
a semiconductor substrate; a laminate including insulating films and conductive films alternately formed above the semiconductor substrate; a silicon pillar formed through the laminate to have a tapered cross-section; a tunnel insulating film disposed on a surface of the silicon pillar facing the laminate; a charge accumulating layer disposed on a surface of the tunnel insulating film facing the laminate; and a block insulating film disposed on a surface of the charge accumulating layer facing the laminate and in contact with the conductive film, wherein, when a voltage is applied on the conductive film during a data deletion operation for the nonvolatile semiconductor memory device, the potential of the silicon pillar with respect to the conductive film decreases as the cross-sectional area of the silicon pillar becomes smaller.