Selective growth of silicon oxide or silicon nitride on silicon surfaces in the presence of silicon oxide
Methods and apparatuses for selectively depositing silicon-containing dielectric or metal-containing dielectric material on silicon or metal surfaces selective to silicon oxide or silicon nitride materials are provided herein. Methods involve exposing the substrate to an acyl chloride which is reactive with the silicon oxide or silicon nitride material where deposition is not desired to form a ketone structure that blocks deposition on the silicon oxide or silicon nitride material. Exposure to the acyl chloride is performed prior to deposition of the desired silicon-containing dielectric material or metal-containing dielectric material.
1. A method for selectively depositing a silicon-containing dielectric material on an exposed first surface of a substrate, the method comprising:
providing the substrate having the exposed first surface, and an exposed second surface,
the exposed first surface having a material selected from the group consisting of polysilicon, amorphous silicon, metals, and silicon nitride having single secondary amine terminated groups, and
the exposed second surface comprising a silicon-containing material having a surface terminated group selected from the group consisting of hydroxyl and primary amine;
prior to depositing the silicon-containing dielectric material, exposing the substrate to an acyl chloride selectively reactive with the exposed second surface to form blocking groups on the exposed second surface, the acyl chloride having a chemical structure of
wherein R 1 is hydrogen or an alkyl group; and
performing one or more cycles of thermal atomic layer deposition to deposit the silicon-containing dielectric material selectively on the exposed first surface, each cycle comprising:
exposing the substrate to a silicon-containing precursor selected to adsorb onto the exposed first surface of the substrate, and
exposing the substrate to a second reactant to form the silicon-containing dielectric material selectively on the exposed first surface of the substrate.
2. The method of claim 1 , wherein the silicon-containing dielectric material is silicon nitride.
3. The method of claim 2 , wherein the second reactant selected from the group consisting of ammonia and hydrazines having the chemical structure
wherein R 2 , R 3 , R 4 , and R 5 are each hydrogen or an alkyl group.
4. The method of claim 2 , wherein the silicon-containing precursor is selected from the group consisting of silicon halides and aminosilanes.
5. The method of claim 1 , wherein the silicon-containing dielectric material is silicon oxide.
6. The method of claim 5 , wherein the second reactant is a weak oxidant.
7. The method of claim 5 , wherein the second reactant is selected from the group consisting of water, hydrogen peroxide, and ozone.
8. The method of claim 1 , wherein the acyl chloride is acetyl chloride.
9. The method of claim 1 , further comprising, prior to providing the substrate, depositing silicon nitride to form an untreated silicon nitride surface; and exposing the untreated silicon nitride surface to a mixture of ammonia and hydrogen gas and igniting a plasma for a duration between about 1 second and about 10 seconds to form the exposed second surface comprising primary amine groups.
10. The method of claim 9 , wherein the amount of ammonia in the mixture of ammonia and hydrogen is less than about 1% by volume.
11. The method of claim 1 , further comprising, prior to providing the substrate, depositing silicon nitride to form an untreated silicon nitride surface and exposing the untreated silicon nitride surface to a mixture of nitrogen and hydrogen gas and igniting a plasma for a duration between about 1 second and about 10 seconds to form the exposed second surface comprising primary amine groups.
12. The method of claim 11 , wherein the amount of nitrogen in the mixture of nitrogen and hydrogen is less than about 1% by volume.
13. The method of claim 1 , wherein the exposed second surface comprises surface terminated primary amine groups of silicon nitride deposited by chemical vapor deposition at a deposition temperature greater than about 500° C.