Self-aligned borderless contacts using a photo-patternable dielectric material as a replacement contact
A photo-patternable dielectric material is provided to a structure which includes a substrate having at least one gate structure. The photo-patternable dielectric material is then patterned forming a plurality of sacrificial contact structures adjacent the at least one gate structure. A planarized middle-of-the-line dielectric material is then provided in which an uppermost surface of each of the sacrificial contact structures is exposed. Each of the exposed sacrificial contact structures is then removed providing contact openings within the planarized middle-of-the-line dielectric material. A conductive metal-containing material is formed within each contact opening.
1. A semiconductor structure comprising:
at least one gate structure located on a surface of a substrate, wherein metal semiconductor alloy portions are located adjacent to the at least one gate structure; and
a middle-of-the-line dielectric material located on at least exposed portions of the substrate and atop the at least one gate stack, wherein the middle-of-the-line dielectric material comprises at least one conductive metal contact that has a bottom contact portion having a bottommost surface in contact with a surface of at least one of the metal semiconductor alloy portions, and an upper contact portion having a portion that partially extends onto and is in direct physical contact with an uppermost surface of a spacer that is present on a vertical sidewall of the at least one gate structure, wherein said upper contact portion has an outermost vertical sidewall surface that is entirely positioned between inner and outer vertical sidewalls of said spacer.
2. The semiconductor structure of claim 1 , wherein said gate structure comprises a finFET gate structure.
3. The semiconductor structure of claim 1 , wherein said gate structure comprises a semiconductor nanowire gate structure.
4. The semiconductor structure of claim 1 , wherein said at least one conductive metal contact comprises a conductive metal-containing material selected from the group consisting of Cu, W and Al.
5. The semiconductor structure of claim 1 , wherein said middle-of-the-line dielectric material is selected from the group consisting of silicon dioxide, undoped silicate glass (USG), fluorosilicate glass (FSG), borophosphosilicate glass (BPSG), and a low-k dielectric layer.
6. The semiconductor structure of claim 1 , wherein said substrate is a bulk semiconductor substrate or a semiconductor-on-insulator.
7. The semiconductor structure of claim 1 , wherein each of said metal semiconductor alloy portions comprises one of Ti, Ni, Pt, W, Co, and Ir.
8. The semiconductor structure of claim 1 , wherein said spacer comprises a dielectric insulating material selected from the group consisting of silicon oxide, silicon nitride, silicon oxynitride, boron nitride, and silicon boron nitride.
9. The semiconductor structure of claim 1 , wherein said at least one gate structure comprises a material stack of, from bottom to top, a gate dielectric layer portion, and a gate conductor layer portion.
10. The semiconductor structure of claim 9 , wherein said material stack further comprises a hard mask material layer portion.
11. The semiconductor structure of claim 1 , wherein said upper contact portion does not extend on an uppermost surface of the at least one gate structure.
12. The semiconductor structure of claim 1 , wherein said bottom contact portion having sidewalls that are vertically aligned with sidewalls of said metal semiconductor alloy portions.