Granted Patent B2

US 7,572,666 · App. 10/438,146 · Granted Aug 11, 2009

Abstract

Claims (50)

1. A method, comprising:

forming a spacer over an electrode material;

covering said spacer with a cover;

removing the spacer to form an opening in said cover; and

forming a memory material in the opening and contacting the electrode material.

2. The method of claim 1 , forming a memory material in the opening includes forming a chalcogenide material in the opening and wherein forming a spacer includes forming polycrystalline silicon over the electrode material.

3. The method of claim 1 , further comprising:

forming a first dielectric material over the electrode;

forming a second dielectric material over the electrode and the first dielectric; and

patterning the second dielectric material into a body, a thickness of the body of the second dielectric material defining a side wall, wherein forming the spacer includes forming the spacer along the side wall and over the electrode material.

4. The method of claim 3 , further comprising:

forming a third dielectric material over the electrode, the spacer and the second dielectric material.

5. The method of claim 3 , wherein removing the spacer to form an opening includes removing the spacer to form an opening to expose a portion of the first dielectric layer, wherein a diameter of the opening is substantially equal to the thickness of the spacer.

6. The method of claim 5 , further comprising removing a portion of the first dielectric layer to expose an upper surface of the electrode through the opening.

7. The method of claim 3 , wherein the first dielectric material has a different etch characteristic than second dielectric layer and wherein the second dielectric material has a different etch characteristic than the spacer.

8. The method of claim 1 , wherein forming a spacer includes forming a spacer having a thickness of less than about 500 Å.

9. The method of claim 1 , further comprising forming a first dielectric material having an edge portion over the electrode, wherein forming the spacer includes forming the spacer along the edge of the first dielectric material.

10. The method of claim 1 , further comprising:

forming a first address line coupled to the memory material via the electrode; and

forming a second address line coupled to the memory material, wherein the second address line is substantially orthogonal to the first address line.

11. The method of claim 10 , wherein the first address line is N-type doped silicon and the second address line includes aluminum.

12. The method of claim 10 , further comprising:

forming a first barrier material between the memory material and the second address line; and

forming a second barrier material between the first barrier material and the second address line.

13. The method of claim 12 , wherein the first barrier material is titanium (Ti) and the second barrier material is titanium nitride (TiN).

14. The method of claim 10 , further comprising forming an isolation device coupled between the electrode and the first address line.

15. A method, comprising:

forming a memory material; and

forming an electrode in electrical communication with the memory material, wherein a contact area between the electrode and the memory material is less than a surface area of an upper surface of the electrode, wherein forming an electrode includes:

forming a first dielectric material having a side wall over the electrode;

forming a spacer over the electrode adjacent to the side wall and over the electrode, wherein the spacer has a different etch characteristic than the first dielectric material;

removing the spacer to form an opening, wherein a diameter of the opening is substantially equal to a thickness of the spacer;

forming a second dielectric material over the electrode, the spacer and the first dielectric material, wherein a portion of the opening is defined by the first dielectric material and the second dielectric material; and

forming the memory material in the opening and contacting the electrode material, wherein the size of the contact area is substantially equal to the thickness of the spacer.

16. The method of claim 15 , wherein forming a memory material includes forming a phase change material.

17. The method of claim 15 , wherein forming a spacer includes forming a polycrystalline silicon layer over the electrode.

18. The method of claim 15 , wherein forming a spacer includes forming a spacer having thickness of less than about 500 Å.

19. The method of claim 15 , wherein forming the electrode includes:

forming a first barrier material; and

forming a second barrier material over the first barrier material, wherein an upper surface of the second barrier material forms the upper surface of the electrode.

20. The method of claim 19 , wherein the first barrier material is titanium silicide (TiSi 2 ) and the second barrier material is titanium nitride (TiN).

21. The method of claim 15 , further comprising:

forming a first address line coupled to the memory material via the electrode; and

forming a second address line coupled to the memory material, wherein the second address line is substantially orthogonal to the first address line.

22. The method of claim 21 , wherein the first address line is N-type doped silicon and the second address line includes aluminum.

23. The method of claim 21 , further comprising:

forming a first barrier material between the memory material and the second address line; and

forming a second barrier material between the first barrier material and the second address line.

24. The method of claim 23 , wherein the first barrier material is titanium (Ti) and the second barrier material is titanium nitride (TiN).

25. The method of claim 21 , further comprising forming an isolation device coupled between the electrode and the first address line.

Assignments (8)