Semiconductor device and manufacturing method thereof

1. A semiconductor device, comprising:

a first bottom electrode layer having two opposite sidewalls;

a barrier layer on a bottom surface and on the two opposite sidewalls of the first bottom electrode layer;

a resistive layer disposed above the first bottom electrode layer, extending past at least one of the two opposite sidewalls of the first bottom electrode layer, and having a variable resistance;

a second bottom electrode layer between the first bottom electrode layer and the resistive layer and extending past at least one of the two opposite sidewalls of the first bottom electrode layer;

a top electrode disposed above the resistive layer and extending past at least one of the two opposite sidewalls of the first bottom electrode; and

an insulating film in contact with the first bottom electrode layer.

2. The semiconductor device of claim 1 , wherein the barrier layer surrounds the opposite sidewalls of the first bottom electrode layer.

3. The semiconductor device of claim 1 , wherein the barrier layer is in contact with a bottom surface of the second bottom electrode layer.

4. The semiconductor device of claim 1 , wherein the second bottom electrode layer is disposed between the resistive layer and the barrier layer to separate the resistive layer and the barrier layer.

5. The semiconductor device of claim 1 , wherein the second bottom electrode layer has a sidewall that aligns with the barrier layer.

6. The semiconductor device of claim 1 , further comprising an insulating structure disposed adjacent to the first and second bottom electrode layers, wherein the insulating structure is in contact with at least one of the two opposite sidewalls of the second bottom electrode layer.

7. The semiconductor device of claim 6 , wherein the resistive layer is in contact with the insulating structure.

8. The semiconductor device of claim 1 , further comprising an insulating structure disposed adjacent to the first and second bottom electrode layers and in contact with the second bottom electrode layer and the barrier layer.

9. The semiconductor device of claim 8 , wherein the insulating structure is separated from the first bottom electrode layer.

10. The semiconductor device of claim 1 , further comprising an upper metal interconnect layer electrically connected to the top electrode and extending past at least one of the two opposite sidewalls of the first bottom electrode layer.

11. The semiconductor device of claim 10 , further comprising an active device electrically connected to the first bottom electrode unit.

12. A semiconductor device, comprising:

a first bottom electrode unit and a second bottom electrode unit spaced apart from the first bottom electrode unit;

a resistive layer disposed above and in contact with the first bottom electrode unit and the second bottom electrode unit, having a variable resistance, wherein a sidewall of the resistive layer is substantially coplanar with at least one of sidewalls of the first and second bottom electrode units; and

a top electrode disposed above the resistive layer, wherein each of the first and second bottom electrode units comprises a first bottom electrode layer and a second bottom electrode layer that is between the first bottom electrode layer and the resistive layer and that extends past a sidewall of the first bottom electrode layer.

13. The semiconductor device of claim 12 , further comprising an insulating structure disposed between the first bottom electrode unit and the second bottom electrode unit.

14. The semiconductor device of claim 13 , wherein the insulating structure is in contact with the first bottom electrode unit, the second bottom electrode unit, and the resistive layer.

15. A method for manufacturing a semiconductor device comprising:

forming an insulating structure;

patterning the insulating structure to form at least one through hole therein, wherein the through hole extends along a first direction;

forming a bottom electrode strip in the through hole of the insulating structure;

forming a resistive film on and in contact with the bottom electrode strip, wherein the resistive film has a variable resistance;

forming a top electrode film on the resistive film; and

patterning the top electrode film, the resistive film, and the bottom electrode strips to form at least one trench in the top electrode film, the resistive film, and the bottom electrode strips, wherein the trench extends along a second direction intersecting the first direction with an angle.

16. The method of claim 15 , wherein the forming the bottom electrode strips comprises:

conformally forming a barrier electrode in the through holes of the insulating structure; and

forming a first bottom electrode layer on the barrier electrode.

17. The method of claim 15 , further comprising conformally forming an insulating film on the patterned top electrode film, the resistive film, and the bottom electrode strips.

18. The method of claim 15 , further comprising forming an upper metal interconnect layer electrically connected to the patterned top electrode film.

19. The method of claim 16 , wherein the forming the resistive film comprises forming the resistive film on and in contact with the insulating structure.

20. The method of claim 16 , wherein the forming the bottom electrode strips further comprises:

removing portions of the first bottom electrode layer and the barrier layer in the through holes of the insulating structure; and

forming a second bottom electrode layer on the first bottom electrode layer and the barrier layer.