Semiconductor storage device

A semiconductor storage device, comprising:

• a laminated body on a substrate, the laminated body comprising conductive layers alternating with insulating layers in a first direction;
• a column extending into the laminated body in the first direction, the column including:
• a first semiconductor film extending along the column in the first direction;
• and
• a first insulating film extending along the column in the first direction, the first insulating film being between the conductive layers and the first semiconductor film, wherein
• the first semiconductor film includes:
• a first section corresponding in position along the first direction to a first conductive layer among the conductive layers in the laminated body that is a farthest layer from the substrate in the first direction;
• and
• a second section between the first section and the substrate in first direction, and
• an average grain diameter of the first section is smaller than an average grain diameter of the second section.

A semiconductor storage device, comprising:

• a laminated body on a substrate, the laminated body comprising conductive layers alternating with insulating layers in a first direction;
• a plurality of columns extending into the laminated body in the first direction, each column including:
• a first polycrystalline semiconductor film extending along the column in the first direction;
• and
• a first insulating film extending along the column in the first direction, the first insulating film being between the conductive layers and the first polycrystalline semiconductor film, wherein
• the first polycrystalline semiconductor film includes:
• a first section corresponding in position along the first direction to a first conductive layer among the conductive layers in the laminated body that is a farthest layer from the substrate in the first direction;
• and
• a second section between the first section and the substrate in the first direction, and
• an average grain diameter of the first section is smaller than an average grain diameter of the second section.