Methods of curing non-carbon flowable CVD films

• US 8,449,942 B2
• Filed: 09/28/2010
• Issued: 05/28/2013
• Est. Priority Date: 11/12/2009
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Liang, Jingmei, Hong, Sukwon
• Primary Examiner(s): CHEN, BRET P
• Application Number:
  US12/891,937
• Publication Number:
  US 20110111137A1
• Time in Patent Office: 973 Days
• Field of Search: 427/255.31, 427/255.394, 427/376.1, 427/376.2, 427/376.3
• US Class Current: 427/255.31
• CPC Class Codes: C23C 16/345 Silicon nitride
• 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 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02222 the compound being a silazane
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02326 into a nitride layer, e.g. changing SiN to SiON
• CPC Class Codes: H01L 21/02337 treatment by exposure to a gas or vapour

Abstract

A method of forming a silicon oxide layer is described. The method may include the steps of mixing a carbon-free silicon-containing precursor with a radical-nitrogen-and/or-hydrogen precursor, and depositing a silicon-nitrogen-and-hydrogen-containing layer on a substrate. The conversion of the silicon-nitrogen-and-hydrogen-containing layer to a silicon-and-oxygen-containing layer is then initiated by a low temperature anneal (a “cure”) in an ozone-containing atmosphere. The conversion of the silicon-and-nitrogen film to silicon oxide in the ozone-containing atmosphere may be incomplete and augmented by a higher temperature anneal in an oxygen-containing environment.

Claims

1. A method of forming a silicon oxygen layer on a substrate in a plasma-free substrate processing region in a substrate processing chamber, the method comprising:

depositing a carbon-free silicon-nitrogen-and-hydrogen-containing layer on the substrate; and

curing the silicon-nitrogen-and-hydrogen-containing layer at a curing temperature in an ozone-containing atmosphere to convert the silicon-nitrogen-and-hydrogen-containing layer into the silicon oxide layer, wherein the curing temperature is increased during the curing operation from a temperature below or about 250°

C. to a higher temperature above 400°

C. to further convert the carbon-free silicon-nitrogen-and-hydrogen-containing layer to the silicon oxide layer.

2. The method of claim 1 wherein the carbon-free silicon-nitrogen-and-hydrogen-containing layer is formed by:

flowing a nitrogen-and/or-hydrogen-containing precursor into a plasma region to produce a radical-nitrogen-and/or-hydrogen precursor;

combining a carbon-free silicon-containing precursor with the radical-nitrogen-and/or-hydrogen precursor in the plasma-free substrate processing region; and

depositing the carbon-free silicon-nitrogen-and-hydrogen-containing layer on the substrate.

3. The method of claim 2 wherein the nitrogen-and/or-hydrogen-containing gas comprises at least one of N₂H₂, NH₃, N₂ and H₂.

4. The method of claim 2 wherein the nitrogen-and/or-hydrogen-containing precursor contains nitrogen and the carbon-free silicon-containing precursor is essentially nitrogen-free.

5. The method of claim 2 wherein the nitrogen-and/or-hydrogen-containing precursor is nitrogen-free and the carbon-free silicon-containing precursor contains nitrogen.

6. The method of claim 2 wherein the carbon-free silicon-containing precursor comprises a silicon-and-nitrogen-containing precursor.

7. The method of claim 2 wherein the carbon-free silicon-containing precursor comprises N(SiH₃)₃.

8. The method of claim 2 wherein the carbon-free silicon-nitrogen-and-hydrogen-containing layer comprises Si—

N and Si—

H bonds.

9. The method of claim 2 wherein the plasma region is in a remote plasma system.

10. The method of claim 2 wherein the plasma region is a partitioned portion of the substrate processing chamber separated from the plasma-free substrate processing region by a showerhead.

11. The method of claim 1 wherein the curing temperature is less than or about 400°

C.

12. The method of claim 1 wherein the curing temperature is less than or about 200°

C.

13. The method of claim 1 wherein the ozone-containing atmosphere further comprises steam (H₂O) while the substrate is at the higher temperature.

14. The method of claim 1 further comprising raising a temperature of the substrate to an oxygen anneal temperature above or about 600°

C. in an oxygen-containing atmosphere.

15. The method of claim 14 wherein the oxygen-containing atmosphere comprises one or more gases selected from the group consisting of atomic oxygen, ozone, nitrogen dioxide, and steam (H₂O).

16. The method of claim 1 wherein the substrate is patterned and has a trench having a width of about 50 nm or less.

17. The method of claim 16 wherein the silicon oxide layer in the trench is substantially void-free.

18. The method of claim 1 wherein the silicon oxide consists essentially of silicon and oxygen.