Embedded MRAM device formation with self-aligned dielectric cap

1. A method of fabricating an integrated circuit (IC), the method comprising:

providing a wafer substrate having an embedded memory area interconnect structure and an embedded non-memory area interconnect structure, the memory area interconnect structure comprising metal interconnects formed within a first interlayer dielectric;

recessing a portion of the memory area interconnect structure;

forming a bottom electrode contact on the recessed portion of the memory area interconnect structure, wherein forming the bottom electrode contact on the recessed portion of the memory area interconnect structure comprises:

depositing a dielectric material cap over the memory area interconnect structure, the first interlayer dielectric, the non-memory area interconnect structure, and in the recessed portion of the memory area, wherein the dielectric material cap is self-aligned in the recessed portion of the memory area interconnect structure;

forming a cavity in the dielectric material cap, the cavity formed over the memory area interconnect structure; and

forming the bottom electrode contact in the cavity;

forming a bottom electrode over the bottom electrode contact;

forming a protective dielectric layer over the non-memory area interconnect structure; and

forming memory element stack layers on a portion of the bottom electrode.

2. The method of claim 1 , wherein forming the memory element stack layers over the bottom electrode contact comprises:

depositing the memory element stack layers over the protective dielectric layer and the bottom electrode contact; and

selectively removing portions of the memory element stack layers and bottom electrode contact to form a pillar structure comprising remaining portions of the memory element stack layers and the bottom electrode.

3. The method of claim 2 , wherein selectively removing portions of the memory element stack layers comprises an ion beam etching process.

4. The method of claim 2 , wherein selectively removing portions of the memory element stack layers comprises a reactive ion etching process.

5. The method of claim 1 further comprising:

forming a first top contact over the memory element stack layers; and

forming a second top contact over the non-memory area interconnect structure;

wherein a first height between the first top contact and the memory area interconnect structure is larger than a second height between the second top contact and the non-memory area interconnect structure.

6. The method of claim 1 , wherein a width of the bottom electrode is less than a memory element width of the memory element stack layers.

7. The method of claim 1 , wherein forming the bottom electrode over the bottom electrode contact comprises:

forming a metal cap layer over the dielectric material cap and the bottom electrode contact; and

removing a portion of the metal cap layer over the non-memory area interconnect structure to form the bottom electrode over the bottom electrode contact.

8. A method of fabricating an integrated circuit, the method comprising:

providing a wafer substrate having an embedded memory area interconnect structure and an embedded non-memory area interconnect structure, the memory area interconnect structure comprising metal interconnects formed within a first interlayer dielectric;

recessing a portion of the memory area interconnect structure;

forming a bottom electrode contact on the recessed portion of the memory area interconnect structure, wherein forming the bottom electrode contact on the recessed portion of the memory area interconnect structure comprises:

depositing a dielectric material cap over the memory area interconnect structure, the first interlayer dielectric, the non-memory area interconnect structure, and in the recessed portion of the memory area, wherein the dielectric material cap is self-aligned in the recessed portion of the memory area interconnect structure;

forming a cavity in the dielectric material cap, the cavity formed over the memory area interconnect structure; and

forming the bottom electrode contact in the cavity;

forming a metal cap layer over the dielectric material cap and the bottom electrode contact;

forming a protective dielectric layer over the metal cap layer;

selectively etching the protective dielectric layer over the memory area to expose a portion of the metal cap layer; and

forming memory element stack layers on the exposed portion of the metal cap layer.

9. The method of claim 8 , wherein forming the memory element stack layers over the bottom electrode contact comprises:

depositing the memory element stack layers over the protective dielectric layer and the metal cap layer; and

selectively removing portions of the memory element stack layers and the metal cap layer to form a pillar structure comprising remaining portions of the memory element stack layers and a bottom electrode.

10. The method of claim 9 , wherein selectively removing the uncovered portions of the memory element stack layers comprises an ion beam etching process.

11. The method of claim 9 , wherein selectively removing the uncovered portions of the memory element stack layers comprises a reactive ion etching process.

12. The method of claim 8 further comprising:

forming a first top contact over the memory element stack layers; and

forming a second top contact over the non-memory area interconnect structure;

wherein a first height between the first top contact and the memory area interconnect structure is larger than a second height between the second top contact and the non-memory area interconnect structure.

13. The method of claim 9 , wherein a width of the bottom electrode is less than a memory element width of the memory element stack layers.

14. The method of claim 8 , wherein the memory element stack comprises a magnetic tunnel junction (MTJ) stack.