Patent ID: 8426976

Claim:
A non-volatile semiconductor storage device comprising a plurality of memory strings with a plurality of electrically rewritable memory cells connected in series, each of the memory strings comprising: a columnar semiconductor layer extending in a direction perpendicular to a substrate; a plurality of conductive layers formed at a sidewall of the columnar semiconductor layer via memory layers; and interlayer insulation layers formed above or below the conductive layers, a sidewall of each of the conductive layers facing the columnar semiconductor layer being formed to be inclined such that the distance thereof from a central axis of the columnar semiconductor layer becomes larger at lower position thereof than at upper position thereof, and a sidewall of each of the interlayer insulation layers facing the columnar semiconductor layer being formed to be inclined such that the distance thereof from a central axis of the columnar semiconductor layer becomes smaller at lower position thereof than at upper position thereof.