Silicon oxide gapfill deposition using liquid precursors

1. A method of depositing a silicon oxide film on a substrate disposed in a substrate processing chamber, the substrate having a gap formed between adjacent raised surfaces with a width less than 50 nm, the method comprising:

vaporizing a liquid Si—C—O—H precursor;

providing a flow of the vaporized liquid Si—C—O—H precursor to the substrate processing chamber;

flowing a gaseous oxidizer to the substrate processing chamber;

inductively generating a deposition plasma having an ion density between 5×10 9 and 5×10 10 ions/cm 3 from the precursor and the oxidizer in the substrate processing chamber; and

depositing the silicon oxide film over the substrate and within the gap with the deposition plasma.

2. The method recited in claim 1 wherein the liquid precursor comprises no Si—C bonds.

3. The method recited in claim 1 wherein the liquid precursor comprises a Si—C bond.

4. The method recited in claim 3 wherein the liquid precursor has a CH 3 :Si stoichiometric ratio that exceeds 2.

5. The method recited in claim 1 wherein the gaseous oxidizer is selected from the group consisting of O 2 , N 2 O, H 2 O, and O 3 .

6. The method recited in claim 1 wherein the gap and adjacent raised features form part of a shallow-trench-isolation structure.

7. The method recited in claim 1 wherein the gap and adjacent raised features form part of a premetal dielectric structure or an intermetal dielectric structure.

8. The method recited in claim 1 further comprising densifying the deposited silicon oxide film, wherein densifying comprises:

flowing a densification gas that includes an oxygen-containing gas into the substrate processing chamber;

forming a densification plasma from the densification gas; and

exposing the deposited film to the densification plasma, whereby the silicon oxide film is a substantially stoichiometric SiO 2 film.

9. The method recited in claim 8 wherein the densification gas comprises H 2 and O 2 .

10. The method recited in claim 9 wherein a flow rate of the H 2 is between 200 and 1000 sccm and a flow rate of the O 2 is between 10 and 1000 sccm.

11. The method recited in claim 8 wherein the densification gas comprises N 2 O.

12. The method recited in claim 8 wherein the densification gas comprises H 2 O.

13. The method recited in claim 8 wherein the densification gas comprises O 3 .

14. The method recited in claim 8 wherein the densification plasma is a high-density plasma having an ion density of at least 10 11 ions/cm 3 .

15. The method recited in claim 8 wherein exposing the deposited film to the densification plasma is performed while a pressure within the substrate processing chamber is maintained between 5 and 25 mtorr.

16. The method recited in claim 8 wherein exposing the deposited film to the densification plasma is performed while a temperature within the substrate processing chamber is maintained above 800° C.

17. A method of depositing a silicon oxide film on a substrate disposed in a substrate processing chamber, the substrate having a gap formed between adjacent raised surfaces with a width less than 50 nm, the method comprising:

vaporizing a liquid Si—C—O—H precursor;

providing a flow of the vaporized liquid Si—C—O—H precursor to the substrate processing chamber;

flowing a gaseous oxidizer to the substrate processing chamber;

generating a deposition plasma having an ion density between 5×10 9 and 5×10 10 ions/cm 3 from the precursor and the oxidizer in the substrate processing chamber; and

depositing the silicon oxide film over the substrate and within the gap with the deposition plasma.

18. The method recited in claim 17 wherein the liquid precursor comprises no Si—C bonds.

19. The method recited in claim 17 wherein the liquid precursor comprises a Si—C bond.

20. The method recited in claim 17 wherein the gaseous oxidizer is selected from the group consisting of O 2 , N 2 O, H 2 O, and O 3 .

21. The method recited in claim 17 further comprising densifying the deposited silicon oxide film, wherein densifying comprises:

flowing a densification gas that includes an oxygen-containing gas into the substrate processing chamber;

forming a densification plasma having an ion density of at least 10 11 ions/cm 3 from the densification gas; and

exposing the deposited film to the densification plasma, whereby the silicon oxide film is a substantially stoichiometric SiO 2 film.

22. A method of depositing a silicon oxide film on a substrate disposed in a substrate processing chamber, the substrate having a gap formed between adjacent raised surfaces with a width less than 50 nm and an aspect ratio greater than 4:1, the method comprising:

vaporizing a liquid Si—C—O—H precursor;

providing a flow of the vaporized liquid Si—C—O—H precursor to the substrate processing chamber;

flowing a gaseous oxidizer selected from the group consisting of O 2 , N 2 O, H 2 O, and O 3 to the substrate processing chamber;

inductively generating a deposition plasma having an ion density between 5×10 9 and 5×10 10 from the precursor and the oxidizer in the substrate processing chamber;

depositing the silicon oxide film over the substrate and within the gap with the deposition plasma;

generating a densification plasma from a densification gas that includes an oxygen-containing gas without extinguishing the deposition plasma; and

exposing the silicon oxide film to the densification gas at a pressure between 5 and 25 mtorr and at a temperature greater than 800° C., whereby the silicon oxide film is a substantially stoichiometric SiO 2 film.

23. The method recited in claim 22 wherein the densification gas comprises H 2 and O 2 .

24. The method recited in claim 23 wherein a flow rate of the H 2 is between 200 and 1000 sccm and a flow rate of the O 2 is between 10 and 1000 sccm.