Non-volatile memory cell, non-volatile memory cell array, and method of manufacturing the same
View Patent ↗A stacking structure in which a stacked body ( 21 ) including a first conductive layer ( 13 ), a semiconductor layer ( 17 ), and a second conductive layer ( 18 ) and an interlayer insulating film ( 16 ) are alternately stacked in parallel to a substrate, a plurality of columnar electrodes ( 12 ) arranged so as to penetrated through the stacking structure in a stacking direction, a variable resistance layer ( 14 ) which is disposed between the columnar electrode ( 12 ) and the first conductive layer ( 13 ) and which has a resistance value that reversibly changes according to an application of an electric signal are included. The variable resistance layer ( 14 ) is formed by oxidizing part of the first conductive layer ( 13 ). The variable resistance layer ( 14 ) and an insulating film for electrically separating the semiconductor layer ( 17 ) and the second conductive layer ( 18 ) from the columnar electrode ( 12 ) are simultaneously formed in a single oxidation process.
1. A non-volatile memory cell, comprising:
a columnar electrode disposed perpendicular to a main surface of a substrate;
a first conductive layer disposed parallel to the main surface of the substrate;
a semiconductor layer disposed in contact with said first conductive layer in a stacking direction;
a second conductive layer disposed in contact with said semiconductor layer in the stacking direction;
a variable resistance layer disposed between said columnar electrode and said first conductive layer, said variable resistance layer having a resistance value that reversibly changes according to an application of an electric signal;
an oxide insulating layer disposed between said columnar electrode and said semiconductor layer, said oxide insulating layer comprising a same constituent element as a constituent element of said semiconductor layer; and
an insulating layer disposed between said columnar electrode and said second conductive layer.
2. The non-volatile memory cell according to claim 1 ,
wherein said semiconductor layer is disposed on said first conductive layer,
said second conductive layer is disposed on said semiconductor layer, and
said variable resistance layer comprises a same constituent element as a constituent element of said first conductive layer.
3. The non-volatile memory cell according to claim 2 ,
wherein said variable resistance layer is formed exclusively at an intersection of said columnar electrode and said first conductive layer.
4. The non-volatile memory cell according to claim 2 ,
wherein said variable resistance layer has a degree of oxygen deficiency that increases from an interface between said variable resistance layer and said columnar electrode toward said first conductive layer.
5. The non-volatile memory cell according to claim 1 ,
wherein said second conductive layer comprises a same constituent metal as a constituent metal of said variable resistance layer.
6. The non-volatile memory cell according to claim 1 ,
wherein said variable resistance layer includes a first variable resistance layer and a second variable resistance layer which are stacked in a direction parallel to the main surface of the substrate, said first variable resistance layer having a first metal oxide, and said second variable resistance layer having a second metal oxide of which a degree of oxygen deficiency is larger than a degree of oxygen deficiency of said first metal oxide.
7. The non-volatile memory cell according to claim 6 ,
wherein said first variable resistance layer is formed in contact with a side face of said columnar electrode to cover the side face, and
said second variable resistance layer is formed exclusively at an intersection of said first variable resistance layer and said first conductive layer.
8. The non-volatile memory cell according to claim 1 ,
wherein said semiconductor layer is disposed between said first conductive layer and said second conductive layer in the stacking direction and in contact with both of said first conductive layer and said second conductive layer.
9. The non-volatile memory cell according to claim 1 ,
wherein said oxide insulating layer is disposed at a height same as a height of said semiconductor layer in the stacking direction, and
said insulating layer is disposed at a height same as a height of said second conductive layer in the stacking direction.
10. A non-volatile memory cell array, comprising:
a plurality of columnar electrodes disposed perpendicular to a main surface of a substrate;
a stacking structure in which a plurality of stacked bodies and a plurality of interlayer insulating films are alternately stacked, each of said stacked bodies including: a first conductive layer disposed parallel to the main surface of the substrate; a semiconductor layer disposed in contact with said first conductive layer in a stacking direction; and a second conductive layer disposed in contact with said semiconductor layer in the stacking direction;
a variable resistance layer disposed between said first conductive layer and a corresponding one of said columnar electrodes, said variable resistance layer having a resistance value that reversibly changes according to an application of an electric signal;
an oxide insulating layer disposed between said columnar electrode and said semiconductor layer, said oxide insulating layer comprising a same constituent element as a constituent element of said semiconductor layer; and
an insulating layer disposed between said columnar electrode and said second conductive layer.
11. The non-volatile memory cell array according to claim 10 ,
wherein said semiconductor layer is disposed on said first conductive layer,
said second conductive layer is disposed on said semiconductor layer, and
said variable resistance layer comprises a same constituent element as a constituent element of said first conductive layer.
12. The non-volatile memory cell array according to claim 11 ,
wherein said variable resistance layer is formed exclusively at an intersection of said columnar electrode and said first conductive layer.
13. The non-volatile memory cell array according to claim 11 ,
wherein said variable resistance layer has a degree of oxygen deficiency that increases from an interface between said variable resistance layer and said columnar electrode toward said first conductive layer.
14. The non-volatile memory cell array according to claim 10 ,
wherein said second conductive layer comprises a same constituent metal as a constituent metal of said variable resistance layer.
15. The non-volatile memory cell array according to claim 10 ,
wherein said variable resistance layer includes a first variable resistance layer and a second variable resistance layer which are stacked in a direction parallel to the main surface of the substrate, said first variable resistance layer having a first metal oxide, and said second variable resistance layer having a second metal oxide of which a degree of oxygen deficiency is larger than a degree of oxygen deficiency of said first metal oxide.
16. The non-volatile memory cell array according to claim 15 ,
wherein said first variable resistance layer is formed in contact with a side face of said columnar electrode to cover the side face, and
said second variable resistance layer is formed exclusively at an intersection of said first variable resistance layer and said first conductive layer.
17. The non-volatile memory cell array according to claim 10 ,
wherein said columnar electrodes are arranged at positions distributed in matrix on the main surface of the substrate.
18. The non-volatile memory cell array according to claim 10 ,
wherein said variable resistance layer comprises an oxygen-deficient metal oxide.
19. The non-volatile memory cell array according to claim 10 ,
wherein a constituent metal element of said first conductive layer and said variable resistance layer is tantalum.
20. The non-volatile memory cell array according to claim 10 ,
wherein said semiconductor layer is disposed between said first conductive layer and said second conductive layer in the stacking direction and in contact with both of said first conductive layer and said second conductive layer, in each of said stacked bodies.
21. The non-volatile memory cell array according to claim 10 ,
wherein in each of said stacked bodies,
said oxide insulating layer is disposed at a height same as a height of said semiconductor layer in the stacking direction, and
said insulating layer is disposed at a height same as a height of said second conductive layer in the stacking direction.