Nonvolatile semiconductor memory device and method for manufacturing the same
AssigneeKabushiki Kaisha Toshiba
InventorYoshio Ozawa
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Abstract
On a silicon substrate is formed a stacked body by alternately stacking a plurality of silicon oxide films and silicon films, a trench is formed in the stacked body, an alumina film, a silicon nitride film and a silicon oxide film are formed in this order on an inner surface of the trench, and a channel silicon crystalline film is formed on the silicon oxide film. Next, a silicon oxide layer is formed at an interface between the silicon oxide film and the channel silicon crystalline film by performing thermal treatment in an oxygen gas atmosphere.
Claims8
A method for manufacturing a nonvolatile semiconductor memory device, comprising:
- forming a stacked body by alternately stacking a plurality of first films and second films on a substrate, the second films being formed with a material which is different from a material forming the first films;
- and
- forming a trench in the stacked body;
- forming a charge storage film, a tunnel insulating film, and a channel film made of a silicon crystal in this order on an exposed surface of the second films of an inner surface of the trench;
- and
- forming a silicon oxide layer at an interface between the tunnel insulating film and the channel film by performing thermal treatment in an oxygen gas atmosphere,
- a cavity being formed in the trench when the thermal treatment is performed, the cavity communicating with outside of the trench, and the channel film being exposed to an inner surface of the cavity.
Dependencies are inferred from the claim text.