Semiconductor device and method for manufacturing semiconductor device

A semiconductor device, comprising:

• a semiconductor substrate;
• a back-gate layer formed above the semiconductor substrate;
• a stacked body formed above the back-gate layer and comprising a plurality of insulating layers alternately formed between a plurality of electrode layers, the stacked body having a lowermost electrode layer of the plurality of electrode layers that contains a metal and remaining electrode layers of the plurality of electrode layers other than the lowermost electrode layer;
• a pair of columnar semiconductor layers penetrating the stacked body;
• and
• a semiconductor layer connecting lower portions of the pair of columnar semiconductor layers, the semiconductor layer embedded in a surface of the back-gate layer, wherein
• the material of the plurality of insulating layers contains silicon oxide,
• the material of the lowermost electrode layer contains tungsten or tungsten silicide, and
• the material of the remaining electrode layers contains silicon.

A semiconductor device, comprising:

• a semiconductor substrate;
• a back-gate layer formed on the semiconductor substrate;
• a stacked body comprising a plurality of insulating layers alternately formed between a plurality of electrode layers formed on the back-gate layer, wherein a lowermost electrode layer of the plurality of electrode layers comprises a metal and remaining electrode layers of the plurality of electrode layers other than the lowermost electrode layer do not contain the metal of the lowermost electrode layer;
• a pair of columnar semiconductor layers penetrating the stacked body;
• and
• a semiconductor layer connecting lower portions of the pair of columnar semiconductor layers, the semiconductor layer embedded in a surface of the back-gate layer.