Patent ID: 8569825
Filing Date: 2013-10-29
Classification: H01L

Abstract:
1. A nonvolatile semiconductor storage device comprising: a semiconductor substrate; a plurality of semiconductor films that is stacked while being spaced from each other in a direction vertical to a surface of the semiconductor substrate, above the semiconductor substrate; a plurality of gate dielectric films, each extending in the direction vertical to the surface of the semiconductor substrate and being arranged on side surfaces of the plurality of semiconductor films; and a plurality of semiconductor or conductor pillar members, each extending in the direction vertical to the surface of the semiconductor substrate and facing the plurality of semiconductor films via each of the gate dielectric films, wherein a dielectric constant of a portion of each of the gate dielectric films that does not intersect with the semiconductor films is lower than a dielectric constant of a portion of each of the gate dielectric films that intersects with the semiconductor films.