CURING METHODS FOR SILICON DIOXIDE THIN FILMS DEPOSITED FROM ALKOXYSILANE PRECURSOR WITH HARP II PROCESS

• US 20090061647A1
• Filed: 08/27/2007
• Published: 03/05/2009
• Est. Priority Date: 08/27/2007
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Mallick, Abhijit Basu, Nemani, Srinivas D., Weidman, Timothy W.
• Granted Patent: US 7,745,352 B2
• Time in Patent Office: Days
• US Class Current: 438/773
• 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 21/02175 characterised by the metal H01L21/02197 takes precedence
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• CPC Class Codes: H01L 21/02189 the material containing zirconium, e.g. ZrO2
• CPC Class Codes: H01L 21/02216 the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02337 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/31608 Deposition of SiO2 H01L21/31625, H01L21/31629 and H01L21/31633 take precedence
• CPC Class Codes: H01L 21/31633 Deposition of carbon doped silicon oxide, e.g. SiOC

Abstract

Methods of curing a silicon oxide layer on a substrate are provided. The methods may include the processes of providing a semiconductor processing chamber and a substrate and forming an silicon oxide layer overlying at least a portion of the substrate, the silicon oxide layer including carbon species as a byproduct of formation. The methods may also include introducing an acidic vapor into the semiconductor processing chamber, the acidic vapor reacting with the silicon oxide layer to remove the carbon species from the silicon oxide layer. The methods may also include removing the acidic vapor from the semiconductor processing chamber. Systems to deposit a silicon oxide layer on a substrate are also described.

Claims

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

providing a semiconductor processing chamber and a substrate;

forming a silicon oxide layer overlying at least a portion of the substrate, the silicon oxide layer including carbon species as a byproduct of formation;

introducing an acidic vapor into the semiconductor processing chamber, the acidic vapor reacting with the silicon oxide layer to remove the carbon species from the silicon oxide layer; and

removing the acidic vapor from the semiconductor processing chamber.

2. The method of claim 1 wherein the silicon oxide layer is deposited using an alkoxysilane process.

3. The method of claim 1 wherein the silicon oxide layer is deposited using a plasma CVD process.

4. The method of claim 1 wherein introducing an acidic vapor further comprises flowing HCl gas into the semiconductor processing chamber.

5. The method of claim 4 wherein the HCl gas is flowed with a siloxane precursor.

6. The method of claim 1 wherein introducing an acidic vapor further comprises in situ generation of HCl or CH₃COOH.

7. The method of claim 6 wherein the in situ generation of HCl or CH₃COOH is performed using chloro-siloxane or acetoxy-siloxane.

8. The method of claim 7 wherein the chloro-siloxane is selected from the group comprising dichlorodiethoxysiloxane or chlorotriethoxysiloxane.

9. The method of claim 7 wherein the acetoxy-siloxane is diacetoxydi-tert-butylsilane.

10. The method of claim 1 wherein the acidic vapor catalyzes the removal of an alkoxyl group from an organo-silicon compound in the silicon oxide layer to leave a silanol moiety.

11. The method of claim 1 wherein the vapor is a mixture of acid and water having a water to acid ratio.

12. The method of claim 11 wherein the water to acid ratio is about 100:

1 to about 1;

100.

13. The method of claim 1 wherein the reaction between the acidic vapor and silicon oxide layer is performed between 10 mTorr to atmospheric pressure.

14. The method of claim 1 wherein the reaction between the acidic vapor and silicon oxide layer is performed between 60 degrees C. to 600 degrees C.

15. The method of claim 1 wherein the silicon oxide layer is exposed to the acidic vapor for a period between 1 second and 24 hours.

16. The method of claim 1 wherein a plurality of structures are formed on a surface of the substrate, wherein the structures include gaps and trenches having height to width aspect rations of 7:

1 or more.

17. The method of claim 1 wherein the initially formed silicon oxide layer that includes the carbon species is a flowable silicon oxide layer.

18. The method of claim 1 further comprising annealing the silicon oxide layer subsequent to the introduction of the acidic vapor into the semiconductor processing chamber in order to increase density of the silicon oxide layer.

26. The method of claim 10, wherein the silanol moiety reacts with other silanol moieties present in the silicon oxide layer to form a silicon oxide network.

19. (canceled)

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

providing a semiconductor processing chamber and a substrate;

forming a trench within the substrate;

depositing a first silicon oxide layer to partially fill the trench;

curing the first silicon oxide layer by introducing an acidic vapor into the semiconductor processing chamber, the acidic vapor reacting with the first silicon oxide layer to remove carbon species from the first silicon oxide layer;

depositing a second silicon oxide layer overlying the first silicon oxide layer, the second silicon oxide layer substantially filling the trench; and

annealing the first and the second silicon oxide layers.

21. The method of claim 20 wherein the first silicon oxide layer is flowable.

22. The method of claim 20 wherein the anneal process increases the density of the first and the second silicon oxide layers.

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

(a) providing a substrate and a semiconductor processing chamber;

(b) forming a trench within the substrate;

(c) depositing a silicon oxide layer within the trench;

(d) curing the silicon oxide layer by introducing an acidic vapor into the semiconductor processing chamber, the acidic vapor reacting with the silicon oxide layer to remove carbon species from the silicon oxide layer;

(e) repeating processes (c) and (d) until a desired thickness of silicon oxide is formed within the trench; and

(f) annealing the silicon oxide layers.

24. The method of claim 23 wherein the thickness of the silicon oxide layer is between 5-500 Å

.

25. The method of claim 23 wherein the desired thickness of silicon oxide substantially fills the trench.