Selective growth of SIO2 on dielectric surfaces in the presence of copper
Methods and apparatuses for selectively depositing silicon oxide on surfaces relative to a metal-containing surface such as copper are provided. Methods involve exposing a substrate having hydroxyl-terminated or dielectric surfaces and copper surfaces to a copper-blocking reagent such as an alkyl thiol to selectively adsorb to the copper surface, exposing the substrate to a silicon-containing precursor for depositing silicon oxide, exposing the substrate to a weak oxidant gas and igniting a plasma, or water vapor without plasma, to convert the adsorb silicon-containing precursor to form silicon oxide. Some methods also involve exposing the substrate to a reducing agent to reduce any oxidized copper from exposure to the weak oxidant gas.
1. A method of selectively depositing silicon oxide on a hydroxyl-terminated surface relative to copper on a substrate, the method comprising:
providing the substrate comprising the hydroxyl-terminated surface and exposed copper metal surface;
prior to depositing the silicon oxide, exposing the substrate to a copper-blocking reagent to selectively adsorb onto the exposed copper metal surface;
exposing the substrate to a silicon-containing precursor to adsorb the silicon-containing precursor onto the hydroxyl-terminated surface to form an adsorbed silicon-containing precursor;
exposing the substrate to an oxidizing plasma generated in an environment comprising a weak oxidant to convert the adsorbed silicon-containing precursor to silicon oxide; and
exposing the substrate to a reducing agent to reduce the exposed copper metal surface.
2. The method of claim 1 , wherein the copper-blocking reagent comprises sulfur.
3. The method of claim 1 , wherein the copper-blocking reagent is an alkyl thiol.
4. The method of claim 3 , wherein the copper-blocking reagent is selected from the group consisting of ethane thiol and butane thiol.
5. The method of claim 1 , wherein the copper-blocking reagent is an alkyl thiol having a chemical formula SH(CH 2 ) n CH 3 whereby n is an integer between and including 2 and 12.
6. The method of claim 1 , wherein the silicon-containing precursor is an aminosilane.
7. The method of claim 1 , further comprising, prior to exposing the substrate to the copper-blocking reagent, introducing a second reducing agent to reduce the exposed copper metal surface.
8. The method of claim 1 , wherein the copper-blocking reagent preferentially adsorbs to the exposed copper metal surface to block subsequent deposition of the silicon oxide on the exposed copper metal surface.
9. A method of selectively depositing silicon oxide on a dielectric material relative to copper on a substrate, the method comprising:
providing the substrate comprising the dielectric material and exposed copper metal surface;
prior to depositing the silicon oxide, exposing the substrate to a copper-blocking reagent to selectively adsorb onto the exposed copper metal surface;
exposing the substrate to a silicon-containing precursor to adsorb the silicon-containing precursor onto the dielectric material to form an adsorbed silicon-containing precursor;
exposing the substrate to water vapor to convert the adsorbed silicon-containing precursor to silicon oxide; and
exposing the substrate to a reducing agent to reduce the exposed copper metal surface.
10. The method of claim 9 , wherein the copper-blocking reagent comprises sulfur.
11. The method of claim 9 , wherein the copper-blocking reagent is an alkyl thiol.
12. The method of claim 11 , wherein the copper-blocking reagent is selected from the group consisting of ethane thiol and butane thiol.
13. The method of claim 9 , wherein the copper-blocking reagent is an alkyl thiol having a chemical formula SH(CH 2 ) n CH 3 whereby n is an integer between and including 2 and 12.
14. The method of claim 9 , wherein the copper-blocking reagent preferentially adsorbs to the exposed copper metal surface to block subsequent deposition of the silicon oxide on the exposed copper metal surface.
15. A method of selectively depositing silicon oxide on a dielectric material relative to copper on a substrate, the method comprising:
providing the substrate comprising the dielectric material and exposed copper metal surface;
prior to depositing the silicon oxide, exposing the substrate to a copper-blocking reagent to selectively adsorb onto the exposed copper metal surface;
exposing the substrate to a silicon-containing precursor to adsorb the silicon-containing precursor onto the dielectric material to form an adsorbed silicon-containing precursor; and
exposing the substrate to an oxidizing plasma generated in an environment comprising a weak oxidant to convert the adsorbed silicon-containing precursor to silicon oxide.
16. The method of claim 15 , wherein the copper-blocking reagent comprises sulfur.
17. The method of claim 15 , wherein the copper-blocking reagent is an alkyl thiol.
18. The method of claim 17 , wherein the copper-blocking reagent is selected from the group consisting of ethane thiol and butane thiol.
19. The method of claim 15 , wherein the copper-blocking reagent is an alkyl thiol having a chemical formula SH(CH 2 ) n CH 3 whereby n is an integer between and including 2 and 12.
20. The method of claim 15 , wherein the copper-blocking reagent preferentially adsorbs to the exposed copper metal surface to block subsequent deposition of the silicon oxide on the exposed copper metal surface.