Nonvolatile semiconductor storage apparatus and method for manufacturing the same
According to an aspect of the present invention, there is provided a nonvolatile semiconductor storage apparatus including: a substrate; a columnar semiconductor disposed perpendicular to the substrate; a charge storage laminated film disposed around the columnar semiconductor; a first conductor layer that is in contact with the charge storage laminated film and that has a first end portion having a first end face; a second conductor layer that is in contact with the charge storage laminated film, that is separated from the first conductor layer and that has a second end portion having a second end face; a first contact plug disposed on the first end face; and a second contact plug disposed on the second end face.
1. A nonvolatile semiconductor storage apparatus comprising:
a substrate;
an insulating layer disposed on the substrate;
a columnar semiconductor disposed perpendicular to the substrate;
a laminated film comprising:
a first insulating film disposed around the columnar semiconductor,
a charge storage film disposed around the first insulating film, and
a second insulating film disposed around the charge storage film;
a first conductor layer that is disposed on the insulating layer and that is in contact with the laminated film;
a first interlayer insulating layer disposed on the first conductor layer;
a second conductor layer that is disposed on the first interlayer insulating layer and that is in contact with the laminated film;
a first contact plug that is connected to the first conductor layer; and
a second contact plug that is connected to the second conductor layer;
wherein the first conductor layer comprises a first end portion that is bent upwardly in a direction perpendicular to a surface of the substrate;
wherein the second conductor layer comprises a second end portion that is bent upwardly in the direction perpendicular to a surface of the substrate;
wherein the first end portion comprises a first end face;
wherein the second end portion comprises a second end face;
wherein the first contact plug is disposed on the first end face; and
wherein the second contact plug is disposed on the second end face.
2. The nonvolatile semiconductor storage apparatus according to claim 1 , wherein the columnar semiconductor, the laminated film and the first conductor layer form a first memory cell that operates in a depression mode; and
wherein the columnar semiconductor, the laminated film and the second conductor layer form a second memory cell that operates in the depression mode.
3. The nonvolatile semiconductor storage apparatus according to claim 2 , wherein the first memory cell and the second memory cell form a memory string.
4. The nonvolatile semiconductor storage apparatus according to claim 1 , wherein the first end face has a width that is equal to or larger than a thickness of the first conductor layer.
5. The nonvolatile semiconductor storage apparatus according to claim 1 , wherein the second end face is disposed in the same plane as and the first end face.
6. The nonvolatile semiconductor storage apparatus according to claim 1 , wherein the first conductor layer further comprise a first central portion where the first conductor layer is in contact with the laminated film; and
wherein the first end portion is made of the same material as the first central layer.
7. The nonvolatile semiconductor storage apparatus according to claim 1 , wherein the first end portion forms an angle that is equal to or larger than 45 degree with a surface of the substrate.
8. The nonvolatile semiconductor storage apparatus according to claim 6 , wherein the insulating layer comprises:
a concave portion that is in contact with the first central portion, and
a convex portion that is in contact with the first end portion.
9. The nonvolatile semiconductor storage apparatus according to claim 1 , wherein the first end portion has a straight shape.
10. The nonvolatile semiconductor storage apparatus according to claim 1 , wherein the first end portion has a curved shape.