Self-aligned contact for replacement metal gate and silicide last processes

1. A device comprising:

a substrate;

an STI region in a portion of the substrate;

a first high-k metal gate stack having first spacers, on the substrate between source/drain regions;

a second high-k metal gate stack having second spacers on the STI region;

a substantially entirely planar Al 2 O 3 or HfO 2 etch stop layer disposed directly in contact with: an upper surface of the first and second high-k metal gate stacks, an upper surface of the first spacers, and an upper surface of the second spacers, the etch stop layer having an opening over a portion of the second high-k metal gate stack;

a pair of third spacers on the etch stop layer over the first high-k metal gate stack;

a pair of fourth spacers on the etch stop layer on the second high-k metal gate stack;

an ILD between the third spacers;

a first contact on the first high-k metal gate stack and over a portion of the first spacers; and

a second contact between and over a portion of the fourth spacers.

2. The device according to claim 1 , further comprising a silicide on the source/drain regions.

3. The device according to claim 2 , wherein the silicide comprises nickel silicide.

4. The device according to claim 1 , wherein the etch stop layer has a thickness of 50 Å to 500 Å.

5. The device according to claim 1 , wherein the third and fourth spacers comprise nitride.

6. The device according to claim 1 , wherein the third and fourth spacers have a width of 100 Å to 1000 Å.

7. The device according to claim 1 , wherein a surface of the first and second spacers is planar with a surface of the first and second high-k metal gate stacks.

8. The device according to claim 1 , wherein the third and fourth spacers each have a sidewall with a slope of 50° to 90°.

9. A device comprising:

a substrate;

an STI region in a portion of the substrate;

first and second high-k metal gate stacks on the substrate, each between source/drain regions, and each having first spacers on opposite sides;

a third high-k metal gate stack on the STI region, having second spacers on opposite sides;

a substantially entirely planar Al 2 O 3 or HfO 2 etch stop layer disposed directly in contact with: an upper surface of the first, second, and third high-k metal gate stacks, an upper surface of the first spacers, and an upper surface of the second spacers, the etch stop layer having an opening over a portion of the third high-k metal gate stack;

a pair of third spacers on the etch stop layer over the first high-k metal gate stack;

a pair of fourth spacers on the etch stop layer over the second high-k metal gate stack;

a pair of fifth spacers on the etch stop layer on the third high-k metal gate stack;

an ILD between the pair of third spacers and the pair of fourth spacers;

at least one first contact adjacent at least one of the first and second high-k metal gate stacks and partially over at least one of the first spacers; and

a second contact between and over a portion of the fifth spacers,

wherein the first and second high-k metal gate stacks have different gate lengths.

10. The device according to claim 9 , further comprising a silicide on the source/drain regions.

11. The device according to claim 9 , wherein the etch stop layer has a thickness of 50 Å to 500 Å.

12. The device according to claim 9 , wherein the third and fifth pairs of spacers comprise nitride.

13. The device according to claim 9 , wherein the third and fifth spacers have a width of 100 Å to 1000 Å.

14. The device according to claim 9 , wherein a surface of the first and second spacers is planar with a surface of the first and second high-k metal gate stacks.

15. The device according to claim 9 , wherein the third and fifth spacers each have a sidewall with a slope of 50° to 90°.

16. A device comprising:

a substrate;

an STI region in a portion of the substrate;

first and second high-k metal gate stacks on the substrate, each between source/drain regions, and each having first spacers on opposite sides, the first and second high-k metal gate stacks having different gate lengths;

a third high-k metal gate stack on the STI region, having second spacers on opposite sides;

a silicide on the source/drain regions;

a substantially entirely planar Al 2 O 3 or HfO 2 etch stop layer disposed directly in contact with: an upper surface of the first, second, and third high-k metal gate stacks, an upper surface of the first spacers, and an upper surface of the second spacers, the etch stop layer having an opening over a portion of the third high-k metal gate stack;

a pair of nitride third spacers having a width of 100 Å to 1000 Å on the etch stop layer over the first high-k metal gate stack;

a pair of nitride fourth spacers having a width of 100 Å to 1000 Å on the etch stop layer over second high-k metal gate stack;

a pair of nitride fifth spacers having a width of 100 Å to 1000 Å on the etch stop layer over the third high-k metal gate stack;

an ILD between the pair of third spacers and the pair of fourth spacers;

a first contact between the first and second high-k metal gate stacks and partially over at least one of the first spacers;

a second contact adjacent one of the first and second high-k metal gate stacks; and

a third contact between and over a portion of the fifth spacers.