Atomic layer deposition of silicon carbon nitride based materials
A process for depositing a silicon carbon nitride film on a substrate can include a plurality of complete deposition cycles, each complete deposition cycle having a SiN sub-cycle and a SiCN sub-cycle. The SiN sub-cycle can include alternately and sequentially contacting the substrate with a silicon precursor and a SiN sub-cycle nitrogen precursor. The SiCN sub-cycle can include alternately and sequentially contacting the substrate with carbon-containing precursor and a SiCN sub-cycle nitrogen precursor. The SiN sub-cycle and the SiCN sub-cycle can include atomic layer deposition (ALD). The process for depositing the silicon carbon nitride film can include a plasma treatment. The plasma treatment can follow a completed plurality of complete deposition cycles.
1. A method for forming a film on a substrate comprising:
performing a plurality of SiCN deposition cycles comprising alternately and sequentially contacting the substrate with a first vapor-phase silicon precursor comprising two silicon atoms bound to a hydrocarbon in an —Si—R—Si— structure, where R comprises a C 1 to C 8 hydrocarbon, and a second vapor-phase nitrogen reactant; and
subsequently exposing the substrate to a hydrogen-containing plasma generated from a reactant gas that comprises H 2 ,
wherein the film has a wet etch rate of less than about 1 nm/min in a dilute aqueous solution of hydrofluoric acid having a concentration of 0.5 weight %.
2. The method of claim 1 , wherein the plurality of deposition cycles are part of a thermal atomic layer deposition (ALD) process.
3. The process of claim 1 , wherein the thin film is deposited at a temperature of 300 to 600° C.
4. The method of claim 1 , wherein the reactant gas comprises a noble gas.
5. The method of claim 4 , wherein the reactant gas comprises one or more of N 2 and Ar.
6. The method of claim 1 , wherein the substrate is exposed to the hydrogen-containing plasma for at least 30 seconds.
7. The method of claim 1 , wherein the hydrogen-containing plasma is generated by applying RF power from about 100 W to about 500 W to the reactant gas.
8. The method of claim 1 , wherein exposing the substrate to the hydrogen-containing plasma comprises a plurality of plasma treatment cycles in which the plasma is turned on for a first duration of time and turned off for a second duration of time.
9. The method of claim 8 , wherein the duration of time in which the plasma is turned on differs in two or more cycles.
10. The method of claim 1 , wherein the deposited thin film comprises carbon.
11. The method of claim 1 , wherein the nitrogen reactant is NH 3 .
12. The method of claim 1 , wherein the silicon precursor is a halogen substituted silylalkane.
13. The method of claim 1 , wherein the silicon precursor comprises an unsubstituted silylalkane.
14. The method of claim 1 , wherein the silicon precursor comprises bis(silyl)alkane, tris(silyl)alkane, tetrakis(silyl)alkane, bis(trichlorosilyl)methane (BTCSMe) or 1,2-bis(trichlorosilyl)ethane (BTCSEt).
15. A method for forming a film on a substrate comprising:
performing one or more SiCN deposition cycles each comprising:
alternately and sequentially contacting the substrate with a first vapor-phase silicon precursor comprising two silicon atoms bound to a hydrocarbon, and a second vapor-phase nitrogen reactant; and
subsequently exposing the substrate to a hydrogen-containing plasma generated from a reactant gas that comprises H 2 ,
wherein the plasma-treated film has a wet etch rate that is less than about 50% of the wet etch rate of thermal silicon oxide, as measured in dilute hydrofluoric acid having a concentration of 0.5 weight %.
16. The method of claim 15 , wherein the reactant gas comprises a noble gas.
17. The method of claim 15 , wherein the silicon precursor comprises two silicon atoms bound to a hydrocarbon in an —Si—R—Si— structure, where R comprises a C 1 to C 8 hydrocarbon.
18. The method of claim 15 , wherein exposing the substrate to the hydrogen-containing plasma comprises a plurality of plasma treatment cycles in which the plasma is turned on for a first duration of time and turned off for a second duration of time.
19. The method of claim 15 , wherein the substrate is exposed to the hydrogen-containing plasma for at least 30 seconds.
20. The method of claim 15 , wherein the hydrogen-containing plasma is generated by applying RF power from about 100 W to about 500 W to the reactant gas.