Semiconductor device and manufacturing method thereof

A semiconductor device comprising:

• a substrate;
• a stacked film including a plurality of first electrode layers disposed over the substrate, the first electrode layers separated from each other in a first direction and including a plurality of second electrode layers disposed over the first electrode layers and separated from each other in the first direction, and
• a first insulating film and a second insulating film:
• that penetrate the plurality of first electrode layers and the plurality of second electrode layers in the first direction,
• extend in a second direction intersecting the first direction, and
• divide the plurality of first electrode layers and the plurality of second electrode layers in a third direction, the third direction intersecting the first direction,
• wherein the stacked film further includes a third insulating film including a first portion, the first portion disposed between the substrate and a lowermost layer of the plurality of first electrode layers, and includes a second portion connected to the first portion, the second portion penetrating the plurality of first electrode layers in the first direction, the second portion extending in the second direction, and dividing the plurality of first electrode layers in the third direction, between the first insulating film and the second insulating film.