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 method of forming a semiconductor structure comprising:
providing at least one gate stack on a surface of a substrate, wherein metal semiconductor alloy portions are located adjacent to the at least one gate stack;
forming a photo-patternable dielectric material on said at least one gate stack, said metal semiconductor alloy portions and exposed portions of the substrate, wherein the photo-patternable dielectric material comprises a functionalized polymer, copolymer or blend including at least two of any combination of polymers and/or copolymers having one or more acid-sensitive imagable groups;
patterning the photo-patternable dielectric material by employing a direct pattern-wise exposure step and without utilizing a pattern transfer etch to provide a sacrificial contact structure comprising a remaining portion of the photo-patternable dielectric material located directly on a surface of at least one of the metal semiconductor alloy portions;
forming a planarized middle-of-the-line dielectric material, wherein an uppermost surface of the sacrificial contact structure is exposed;
removing the exposed sacrificial contact structure to provide a contact opening; and
filling the contact opening with a conductive metal-containing material, wherein said conductive metal-containing material forms a metal contact.
2. The method of claim 1 , wherein the polymers include one monomer and the copolymers include at least two monomers and wherein the monomers of the polymers and the monomers of the copolymers are selected from a siloxane, silane, carbosilane, oxycarbosilane, silsesquioxane, alkyltrialkoxysilane, tetra-alkoxysilane, unsaturated alkyl substituted silsesquioxane, unsaturated alkyl substituted siloxane, unsaturated alkyl substituted silane, an unsaturated alkyl substituted carbosilane, unsaturated alkyl substituted oxycarbosilane, carbosilane substituted silsesquioxane, carbosilane substituted siloxane, carbosilane substituted silane, carbosilane substituted carbosilane, carbosilane substituted oxycarbosilane, oxycarbosilane substituted silsesquioxane, oxycarbosilane substituted siloxane, oxycarbosilane substituted silane, oxycarbosilane substituted carbosilane, and oxycarbosilane substituted oxycarbosilane.
3. The method of claim 1 , wherein said photo-patternable dielectric material comprises hydrogen silsesquioxane.
4. The method of claim 1 , wherein said forming the photo-patternable dielectric material comprises spin-on-coating, dip coating, brush coating, blade coating, chemical solution deposition, or ink-jet dispensing.
5. The method of claim 1 , wherein said forming said planarized middle-of-the-line dielectric material comprises depositing a middle-of-the-line dielectric material and subjecting the middle-of-the-line dielectric material to a planarization and revealing process to expose the sacrificial contact structure.
6. The method of claim 1 , wherein said forming said planarized middle-of-the-line dielectric material comprises depositing a self-planarizing middle-of-the-line dielectric material, planarizing the planarized middle-of-the-line dielectric material and etching back.
7. The method of claim 1 , wherein said removing the exposed sacrificial contact structure comprises using HF as a chemical etch during a wet etch process.
8. The method of claim 1 , wherein said filling the contact opening with the conductive metal-containing material comprises chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), atomic layer deposition (ALD), plasma enhanced ALD, sputtering, chemical solution deposition or plating and said conductive-metal-containing material is selected from Cu, W and Al.
9. The method of claim 1 , wherein said metal contact has an upper portion that extends partially onto an uppermost surface of a spacer that is disposed on vertical sidewalls of the at least one gate structure.
10. A method of forming a semiconductor structure comprising:
providing at least one gate stack on a surface of a substrate;
forming a photo-patternable dielectric material on said at least one gate stack and exposed portions of the substrate, wherein the photo-patternable dielectric material comprises a functionalized polymer, copolymer or blend including at least two of any combination of polymers and/or copolymers having one or more acid-sensitive imagable groups;
patterning the photo-patternable dielectric material by employing a direct pattern-wise exposure step and without utilizing a pattern transfer etch to provide a sacrificial contact structure comprising a remaining portion of the photo-patternable dielectric material located directly on an exposed surface of the substrate;
forming a planarized middle-of-the-line dielectric material, wherein an uppermost surface of the sacrificial contact structure is exposed;
removing the exposed sacrificial contact structure to provide a contact opening;
forming metal semiconductor alloy portions on each side of the at least one gate stack utilizing the planarized middle-of-the-line dielectric material as a mask; and
filling the contact opening with a conductive metal-containing material, wherein said conductive metal-containing material forms a metal contact.
11. The method of claim 10 , wherein the polymers include one monomer and the copolymers include at least two monomers and wherein the monomers of the polymers and the monomers of the copolymers are selected from a siloxane, silane, carbosilane, oxycarbosilane, silsesquioxane, alkyltrialkoxysilane, tetra-alkoxysilane, unsaturated alkyl substituted silsesquioxane, unsaturated alkyl substituted siloxane, unsaturated alkyl substituted silane, an unsaturated alkyl substituted carbosilane, unsaturated alkyl substituted oxycarbosilane, carbosilane substituted silsesquioxane, carbosilane substituted siloxane, carbosilane substituted silane, carbosilane substituted carbosilane, carbosilane substituted oxycarbosilane, oxycarbosilane substituted silsesquioxane, oxycarbosilane substituted siloxane, oxycarbosilane substituted silane, oxycarbosilane substituted carbosilane, and oxycarbosilane substituted oxycarbosilane.
12. The method of claim 10 , wherein said photo-patternable dielectric material comprises hydrogen silsesquioxane.
13. The method of claim 10 , wherein said forming said planarized middle-of-the-line dielectric material comprises depositing a middle-of-the-line dielectric material and subjecting the middle-of-the-line dielectric material to a planarization and revealing process to expose the sacrificial contact structure.
14. The method of claim 10 , wherein said forming said planarized middle-of-the-line dielectric material comprises depositing a self-planarizing middle-of-the-line dielectric material, planarizing the planarized middle-of-the-line dielectric material and etching back.
15. The method of claim 1 , wherein said removing the exposed sacrificial contact structure comprises using HF as a chemical etch during a wet etch process.