Method for forming a metal cap in a semiconductor memory device
View Patent ↗Exemplary embodiments of the present invention are directed towards a method for fabricating a semiconductor memory device comprising selectively depositing a material to form a cap above a recessed cell structure in order to prevent degradation of components inside the cell structure in oxidative or corrosive environments.
1. A method for fabricating a semiconductor memory device comprising:
performing a chemical-mechanical planarization to form a cell structure entirely recessed in a template layer, wherein a top surface of the cell structure is below a top surface of the template layer, forming a recess; and
selectively depositing a material in the recess to form a cap above the cell structure in order to prevent degradation of components inside the cell structure in oxidative or corrosive environments,
wherein the cap is a metal cap, and
wherein the cell structure includes a top electrode and an active cell material.
2. The method of claim 1 , wherein selectively depositing the material to form a cap further comprises:
using one of chemical vapor deposition, atomic layer deposition or selective electroless plating for deposition.
3. The method of claim 1 , further comprising removing the cap using a dry etch method.
4. The method of claim 1 , wherein the cell structure is formed in a trench in the template layer.
5. The method of claim 4 , wherein the cap is formed using one of W, Ti, or Co.
6. The method of claim 1 , further comprising a bottom electrode formed below the cell structure.
7. The method of claim 6 , further comprising a transistor connected to the bottom electrode.
8. The method of claim 6 , wherein the cap covers an entire surface of the top electrode.
9. The method of claim 1 , wherein the top electrode is formed over the active cell material.
10. The method of claim 1 , wherein the cap is deposited in the recess such that it covers an entire surface of the top electrode.
11. A method for fabricating a semiconductor memory device comprising:
performing a chemical-mechanical planarization to form a cell structure entirely recessed in a template layer, wherein a top surface of the cell structure is below a top surface of the template layer, forming a recess; and
selectively depositing a material in the recess to form a cap above the cell structure in order to prevent degradation of components inside the cell structure in oxidative or corrosive environments,
wherein the cell structure includes a top electrode and an active cell material, and
wherein the cap covers an entirety of a surface that includes a portion of the top electrode and a portion of the active cell material.
12. The method of claim 11 , further comprising a bottom electrode formed below the cell structure.
13. The method of claim 12 , further comprising a transistor connected to the bottom electrode.
14. The method of claim 11 , wherein selectively depositing the material to form a cap further comprises:
using one of chemical vapor deposition, atomic layer deposition or selective electroless plating for deposition.
15. The method of claim 11 , further comprising removing the cap using a dry etch method.
16. The method of claim 11 , wherein the cell structure is formed in a trench in a template layer.
17. The method of claim 11 , wherein the cap is a metal cap.
18. The method of claim 17 , wherein the cap is formed using one of W, Ti, or Co.
19. The method of claim 1 , wherein the cap is formed using one of W, Ti, or Co.
20. The method of claim 1 , wherein the cap covers an entirety of a surface that includes a portion of the top electrode and a portion of the active cell material.