Method for depositing and curing low-k films for gapfill and conformal film applications

• US 7,790,634 B2
• Filed: 05/25/2007
• Issued: 09/07/2010
• Est. Priority Date: 05/30/2006
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Nemani, Srinivas D., Munro, Jeffrey C.
• Primary Examiner(s): EVERHART, CARIDAD
• Application Number:
  US11/753,918
• Publication Number:
  US 20080026597A1
• Time in Patent Office: 1,201 Days
• Field of Search: 438/789, 438/794, 438/793, 257/E21.489, 257/E21.493, 257/E21.494, 257/E21.478
• US Class Current: 438/789
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02126 the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/31633 Deposition of carbon doped silicon oxide, e.g. SiOC

Abstract

Methods of making a silicon oxide layer on a substrate are described. The methods may include forming the silicon oxide layer on the substrate in a reaction chamber by reacting an atomic oxygen precursor and a silicon precursor and depositing reaction products on the substrate. The atomic oxygen precursor is generated outside the reaction chamber. The methods also include heating the silicon oxide layer at a temperature of about 600° C. or less, and exposing the silicon oxide layer to an induced coupled plasma. Additional methods are described where the deposited silicon oxide layer is cured by exposing the layer to ultra-violet light, and also exposing the layer to an induced coupled plasma.

Claims

1. A method of making a silicon oxide layer on a substrate, the method comprising:

forming the silicon oxide layer on the substrate in a reaction chamber by reacting atomic oxygen with a silicon precursor and depositing reaction products on the substrate, wherein the atomic oxygen is generated outside the reaction chamber;

heating the silicon oxide layer at a temperature of about 600°

C. or less; and

exposing the silicon oxide layer to an induced coupled plasma.

2. The method of claim 1, wherein the silicon oxide layer is heated to a temperature from about 300°

C. to about 600°

C.

3. The method of claim 1, wherein the silicon oxide layer is heated to about 380°

C.

4. The method of claim 1, wherein the silicon oxide layer is heated for about 1 minute to about 30 minutes.

5. The method of claim 1, wherein the silicon oxide layer is heated for about 1 minute.

6. The method of claim 1, wherein the plasma comprises a helium or argon precursor.

7. The method of claim 1, wherein the silicon oxide layer is heated for about 1 minute to about 30 minutes before being exposed to the induced coupled plasma.

8. The method of claim 1, wherein the silicon oxide layer is heated in the reaction chamber in a nitrogen atmosphere at a pressure of about 15 mTorr to about 760 Torr.

9. The method of claim 8, wherein the pressure is about 50 Torr.

10. The method of claim 1, wherein the silicon oxide layer has a temperature of about 300°

C. to about 600°

C. during the exposure to the plasma.

11. The method of claim 10, wherein the temperature is about 380°

C.

12. The method of claim 1, wherein an RF power source operating at a power level of about 1000 Watts to about 9600 Watts is used to generate the plasma.

13. The method of claim 12, wherein the power level is about 1800 Watts.

14. The method of claim 1, wherein the reaction chamber has a pressure of about 2 mTorr to about 50 mTorr during the exposure of the silicon oxide layer to the plasma.

15. The method of claim 14, wherein the chamber pressure is about 20 mTorr.

16. The method of claim 1, wherein the silicon oxide layer is exposed to the plasma for about 1 minute to about 10 minutes.

17. The method of claim 16, wherein the silicon oxide layer is exposed to the plasma for about 3 minutes.

18. A method of forming a silicon oxide layer on a substrate, the method comprising:

forming the silicon oxide layer on the substrate in a reaction chamber by reacting atomic oxygen with a silicon precursor and depositing reaction products on the substrate, wherein the atomic oxygen is generated outside the reaction chamber;

exposing the silicon oxide layer to ultra-violet light; and

exposing the silicon oxide layer to an induced coupled plasma.

19. The method of claim 18, wherein the silicon oxide layer has a temperature of about 25°

C. to about 900°

C. during the exposure to the ultra-violet light.

20. The method of claim 18, wherein the silicon oxide layer has a temperature of about 300°

C. to about 600°

C. during the exposure to the ultra-violet light.

21. The method of claim 18, wherein the ultra-violet light has a peak wavelength intensity at about 220 nm.

22. The method of claim 18, wherein the silicon oxide is exposed to the ultra-violet light for about 10 second to about 60 minutes.

23. The method of claim 18, wherein the silicon oxide is exposed to the ultra-violet light for about 30 minutes.

24. The method of claim 18, wherein the silicon oxide is exposed to the ultra-violet light in an atmosphere comprising helium, argon, N2, N2O, ammonia, ozone, or H2O.

25. The method of claim 24, wherein the pressure of the atmosphere in the reaction chamber is about 1 Torr to about 600 Torr.

26. A method of depositing and annealing a silicon oxide layer on a wafer substrate, the method comprising:

providing the substrate wafer to an HDP-CVD process chamber where the deposition of the silicon oxide layer occurs;

providing a remote plasma generation unit outside the HDP-CVD process chamber, wherein the remote plasma generation unit is used to generate atomic oxygen that is supplied to the HDP-CVD process chamber;

supplying a silicon precursor to the HDP-CVD process chamber, wherein the silicon precursor and the atomic oxygen react to form the silicon oxide layer on the wafer;

performing a first anneal on the deposited silicon oxide layer, wherein the first anneal comprises heating the layer to a temperature of about 300°

C. to about 600°

C. for about 1 minute to about 30 minutes; and

performing a second anneal on the deposited oxide layer, wherein the second anneal comprises exposing the layer to a high-density argon plasma for about 1 minute to about 10 minutes.

27. The method of claim 26, wherein the first and second anneals are performed in about 4 minutes to about 10 minutes.

28. The method of claim 26, wherein the first anneal is performed for about 1 minute and the second anneal is performed for about 3 minutes.

29. The method of claim 26, wherein the first and second anneals are performed at about 380°

C.

30. The method of claim 26, wherein the silicon precursor is selected from the group consisting of octamethylcyclotetrasiloxane (OMCTS), tetramethoxysilane (TMOS), and a mixture of OMCTS and TMOS.

31. The method of claim 26, wherein the atomic oxygen is generated by plasma dissociated of molecular oxygen in the remote plasma generation unit.

32. The method of claim 26, wherein the substrate wafer is held at a temperature of about 30°

C. to about 75°

C. during the formation of the silicon oxide layer.