Semiconductor memory device and method for manufacturing the same
According to one embodiment, a semiconductor memory device includes a stacked body, a semiconductor pillar, an insulating film, and a charge storage film. The stacked body includes a plurality of electrode films stacked with an inter-layer insulating film provided between the electrode films. The semiconductor pillar pierces the stacked body. The insulating film is provided between the semiconductor pillar and the electrode films on an outer side of the semiconductor pillar with a gap interposed. The charge storage film is provided between the insulating film and the electrode films. The semiconductor pillar includes germanium. An upper end portion of the semiconductor pillar is supported by an interconnect provided above the stacked body.
1. A semiconductor memory device, comprising:
a stacked body including a plurality of electrode films stacked with an inter-layer insulating film provided between the electrode films;
a semiconductor pillar piercing the stacked body;
an insulating film provided between the semiconductor pillar and the electrode films on an outer side of the semiconductor pillar with a gap interposed;
a charge storage film provided between the insulating film and the electrode films; and
a support portion provided on a lower end side of the semiconductor pillar and configured to maintain a distance between the insulating film and the semiconductor pillar,
the semiconductor pillar including germanium,
an upper end portion of the semiconductor pillar being supported by an interconnect provided above the stacked body, and
the support portion including aluminum.
2. The device according to claim 1 , wherein an upper end of the support portion is lower than a lower end of the electrode film of a lowermost layer.
3. The device according to claim 1 , wherein the insulating film and the gap are used as a tunneling insulating film.
4. The device according to claim 1 , comprising a blocking insulating film including aluminum oxide provided between the charge storage film and the electrode films.
5. The device according to claim 1 , wherein:
the semiconductor pillar is multiply provided; and
the device comprises a connection member connecting lower end portions of mutually-adjacent semiconductor pillars.