Semiconductor storage device and manufacturing method thereof

A method of manufacturing a semiconductor storage device, the method comprising:

• forming a memory pillar including a first semiconductor layer that extends in a first direction;
• forming a first insulating layer on the memory pillar;
• forming a groove in the first insulating layer, the groove that extending in a second direction intersecting the first direction, a top portion of the memory pillar being exposed by the groove;
• forming a second semiconductor layer on a sidewall of the groove and the exposed top portion of the memory pillar;
• forming a second insulating layer on the second semiconductor layer;
• removing a part of the second insulating layer and oxidizing a portion of the second semiconductor layer;
• and
• forming a wiring layer in the groove on the second insulating layer and the oxidized portion of the second semiconductor layer.

A semiconductor memory device, comprising:

• a plurality of first wiring layers stacked in a first direction;
• a first memory pillar including a first semiconductor layer on an outer periphery, the first memory pillar extending in the first direction through the plurality of first wiring layers;
• a second wiring above an upper end of the first semiconductor layer in the first direction;
• a second semiconductor layer having a bent shape including a first portion between the first semiconductor layer and the second wiring layer in the first direction and a second portion extending away from the first semiconductor layer;
• and
• a first insulating layer directly on the second semiconductor layer, the first insulating layer being between the first portion and the second wiring in first direction, and between the second portion and the second wiring in a second direction intersecting the first direction.