Semiconductor device and method for manufacturing same

A semiconductor device comprising:

• a film stack including a plurality of electrode layers and a plurality of first insulating films alternately stacked on top of one another;
• a charge storage layer provided between a side face of the electrode layers through a second insulating film;
• and
• a semiconductor layer provided between a side face of the charge storage layer through a third insulating film, wherein
• at least one of the plurality of electrode layers includes a first layer, a second layer, and a third layer,
• the first layer includes tungsten and nitrogen,
• the second layer includes tungsten,
• the third layer includes multiple crystal grains having an average grain diameter equal to or larger than about 50 nanometers (nm), and
• the second layer is provided between the first layer and the third layer.

A semiconductor device manufacturing method, comprising:

• forming a film stack including a plurality of fifth layers and m a plurality of first insulating films alternately stacked on top of one another;
• forming a charge storage layer provided between a side face of the fifth layers through a second insulating film;
• forming a semiconductor layer provided between a side face of the charge storage layer through a third insulating film;
• removing the fifth layers to form multiple first recesses in the film stack;
• and
• forming multiple electrode layers in the first recesses, wherein
• at least one electrode layer of the electrode layers is formed to include a first layer and a second layer,
• the first layer includes tungsten and nitrogen,
• the second layer includes tungsten, and
• the second layer is formed at a temperature less than or equal to about 300° C. using a gas including tungsten and a reducing gas including silicon.