Variable resistance element and method for fabricating the variable resistance element

1. A variable resistance element comprising:

an interlayer insulating film;

a first electrode that is formed inside of the interlayer insulating film, the first electrode including an active electrode, the active electrode including a side surface and a bottom surface, both of which are covered with a barrier metal;

a variable resistance film that is formed on an upper surface of the first electrode;

a second electrode that is formed on the variable resistance film;

an insulating film spacer that is formed between the barrier metal and the variable resistance film,

an insulating barrier film including an opening wherein

the barrier metal is in contact with the insulating film spacer,

the variable resistance film is elongated inside the opening of the insulating barrier film,

a lower face of the variable resistance film is in contact with a surface of the first electrode, and is otherwise in contact with a bottom of the opening of the insulating barrier film, and

a side face of the variable resistance film is in contact with a face of the insulating film spacer.

2. The variable resistance element according to claim 1 , wherein the insulating film spacer is formed with the interlayer insulating film.

3. The variable resistance element according to claim 1 , wherein the insulating film spacer includes at least oxygen and silicon.

4. The variable resistance element according to claim 1 further comprising, in an inside of the interlayer insulating film, a plurality of electrodes including the active electrode a side surface and a bottom surface of which are covered with a barrier metal, wherein the insulating film spacer is disposed between the plurality of electrodes and the variable resistance film, respectively.

5. The variable resistance element according to claim 1 wherein a film thickness of the insulating film spacer is equal to or smaller than 10 nm.

6. The variable resistance element according to claim 1 wherein

the first electrode includes a first acute angle portion,

the second electrode includes a second acute angle portion, and

a distance between the first acute angle portion and the second acute angle portion is a shortest distance in a distance between the first electrode and the second electrode.

7. The variable resistance element according to claim 1 , wherein

the active electrode includes copper,

the second electrode includes at least ruthenium, nitrogen, and a first metal, and

the first metal includes at least one of titanium, tantalum, aluminum, manganese, zirconium, hafnium, magnesium, cobalt, zinc, or tungsten.

8. The variable resistance element according to claim 1

wherein the insulating barrier film is formed on the first electrode and the opening of the insulating barrier film is provided on an upper surface of the first electrode, the opening causing an end of the active electrode to be exposed, wherein

the variable resistance film is formed on an upper surface of the end.

9. The variable resistance element according to claim 8 , wherein the opening has an inverse tapered shape when viewed from a vertically upper side of the insulating barrier film.

10. The variable resistance element according to claim 8 , wherein the barrier metal that covers the end of the first electrode has a tapered shape.

11. The variable resistance element according to claim 1 wherein

the variable resistance film is a laminated film including an oxide layer, and

the oxide layer is in contact with the insulating film spacer.

12. The variable resistance element according to claim 11 , wherein the oxide layer includes at least one of zirconia, hafnia, titania, or magnesia.

13. The variable resistance element according to claim 1 wherein the variable resistance film is a solid electrolyte.