Sequential deposition/anneal film densification method

• US 7,790,633 B1
• Filed: 09/11/2006
• Issued: 09/07/2010
• Est. Priority Date: 10/26/2004
• Status: Active Grant

• Current Assignee: Novellus Systems Incorporated (LAM Research Corporation)
• Original Assignee: Novellus Systems Incorporated (LAM Research Corporation)
• Inventors: Tipton, Adrianne K., Tobin, Jeff, Tarafdar, Raihan M., Papasouliotis, George D., Rulkens, Ron, Hausmann, Dennis M., Nie, Bunsen
• Primary Examiner(s): EVERHART, CARIDAD
• Application Number:
  US11/519,445
• Time in Patent Office: 1,457 Days
• Field of Search: 438/778, 438/788, 438/799, 257/E21.471, 257/E21.475, 257/E21.489, 257/E21.625
• US Class Current: 438/788
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02312 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/02315 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/02345 treatment by exposure to radiation, e.g. visible light
• CPC Class Codes: H01L 21/02348 treatment by exposure to UV light
• CPC Class Codes: H01L 21/02351 treatment by exposure to corpuscular radiation, e.g. exposure to electrons, alpha-particles, protons or ions
• CPC Class Codes: H01L 21/02354 using a coherent radiation, e.g. a laser
• CPC Class Codes: H01L 21/76224 using trench refilling with dielectric materials trench filling with polycristalline silicon H01L21/763; together with vertical isolation, e.g. trench refilling in a SOI substrate H01L21/76264

Abstract

A silicon dioxide-based dielectric layer is formed on a substrate surface by a sequential deposition/anneal technique. The deposited layer thickness is insufficient to prevent substantially complete penetration of annealing process agents into the layer and migration of water out of the layer. The dielectric layer is then annealed, ideally at a moderate temperature, to remove water and thereby fully densify the film. The deposition and anneal processes are then repeated until a desired dielectric film thickness is achieved.

Claims

1. A method of forming a densified dielectric film, the method comprising:

(a) depositing a silicon oxide-based dielectric film layer on a substrate;

(b) annealing the dielectric film layer to remove water and densify the layer, wherein the annealing comprises a treatment with an annealing process agent selected from the group consisting of an oxygen-based plasma treatment and a UV-based treatment; and

(c) repeating (a) and (b) at least once to form the densified dielectric film;

wherein the thickness of the dielectric film layer formed in (a) is insufficient to prevent substantially complete penetration of an annealing process agent into the layer and migration of water out of the layer.

2. The method of claim 1, wherein the film layer thickness is between about 20 Å

and 2 microns.

3. The method of claim 1, wherein the film layer thickness is between about 100 and 3000 Å

.

4. The method of claim 1, wherein (a) comprises a thermal chemical vapor deposition of a silicon-containing precursor.

5. The method of claim 1, wherein (a) comprises an atomic layer deposition process.

6. The method of claim 1, wherein the annealing comprises a UV-based treatment.

7. The method of claim 1, wherein the annealing comprises treatment with an oxygen-containing plasma.

8. The method of claim 1, wherein the (a) and (b) are conducted in situ in a single reactor chamber.

9. The method of claim 1, wherein (a) comprises:

(i) exposing the substrate surface to a catalyst or catalyst-containing precursor gas to form a catalyst on the substrate surface; and

(ii) exposing the substrate surface to a silicon-containing precursor gas to form a silicon oxide-based dielectric film layer on the substrate.

10. The method of claim 9, wherein the silicon-containing precursor is at least one of a silanol and a silanediol.

11. The method of claim 9, wherein the catalyst or catalyst-containing precursor is a metal catalyst-containing precursor selected from the list of metal catalyst-containing precursors comprising aluminum, zirconium, hafnium, gallium, titanium, niobium, tantalum, and combinations thereof.

12. The method of claim 11, wherein the metal catalyst-containing precursor is at least one of hexakis(dimethylamino) aluminum and trimethyl aluminum.

13. The method of claim 1, wherein the annealing is conducted in an oxidizing environment.

14. The method of claim 13, wherein the oxidizing environment comprises one or more of oxygen, ozone, peroxide or nitrous oxide.

15. The method of claim 1, wherein the (a) and (b) are conducted in separate reactor chambers.

16. The method of claim 15, wherein the separate reactor chambers are integrated in a single apparatus.

17. The method of claim 1, wherein the substrate is a partially fabricated semiconductor wafer.

18. The method of claim 17, wherein the dielectric film is deposited over gaps in the partially fabricated semiconductor wafer.

19. A method of forming a densified dielectric film, the method comprising:

(a) exposing a substrate surface to a catalyst or catalyst-containing precursor gas to form a catalyst on the substrate surface;

(b) exposing the substrate surface to a silicon-containing precursor gas to form a silicon oxide-based dielectric film layer on the substrate;

(c) repeating (a) and (b) at least once to form a dielectric film; and

(d) annealing the dielectric film to remove water and densify the film, wherein the annealing comprises a treatment with an annealing process agent selected from the group consisting of an oxygen-based plasma treatment, and a UV-based treatment;

wherein the thickness of the dielectric film formed in (c) is insufficient to prevent substantially complete penetration of an annealing process agent into the film and migration of water out of the film.

20. The method of claim 19, wherein the annealing comprises an oxygen-containing plasma-based treatment.

21. The method of claim 19, wherein the annealing comprises a UV-based treatment.

22. The method of claim 19, wherein the annealing comprises treatment with an oxygen-containing plasma.

23. A method of forming a densified dielectric film, the method comprising:

(a) depositing a silicon oxide-based dielectric film layer on a substrate;

(b) annealing the dielectric film layer to remove water and densify the layer, wherein the annealing comprises a treatment with an annealing process agent selected from the group consisting of an oxygen-based plasma treatment and a UV-based treatment; and

wherein the thickness of the dielectric film layer formed in (a) is insufficient to prevent substantially complete penetration of an annealing process agent into the layer and migration of water out of the layer.