Methods and apparatus for incorporating nitrogen in oxide films
In a first aspect, a first method is provided. The first method includes the steps of (1) preconditioning a process chamber with an aggressive plasma; (2) loading a substrate into the process chamber; and (3) performing plasma nitridation on the substrate within the process chamber. The process chamber is preconditioned using a plasma power that is at least 150% higher than a plasma power used during plasma nitridation of the substrate. Numerous other aspects are provided.
1. A method comprising:
preconditioning a process chamber with an aggressive plasma;
loading a substrate into the process chamber; and
performing plasma nitridation on the substrate within the process chamber;
wherein the process chamber is preconditioned using a plasma power that is at least 150% higher than a plasma power used during plasma nitridation of the substrate.
2. The method of claim 1 wherein preconditioning the process chamber with an aggressive plasma comprises employing a plasma power of about 800 to 2500 watts.
3. The method of claim 1 wherein preconditioning the process chamber with an aggressive plasma comprises preconditioning the process chamber for about 5 to 60 seconds.
4. The method of claim 1 wherein preconditioning the process chamber with an aggressive plasma comprises employing a chamber pressure of about 10 to 100 milliTorr.
5. The method of claim 1 wherein preconditioning the process chamber with an aggressive plasma comprises preconditioning the process chamber with a nitrogen plasma.
6. The method of claim 5 wherein preconditioning the process chamber with a nitrogen plasma comprises preconditioning the process chamber with a gas mixture that includes nitrogen and at least one of helium and argon.
7. The method of claim 5 wherein preconditioning the process chamber with a nitrogen plasma comprises causing nitrogen to be absorbed or adsorbed onto at least one of process kit parts and chamber walls of the process chamber.
8. The method of claim 7 wherein preconditioning the process chamber with a nitrogen plasma comprises saturating at least one of process kit parts and chamber walls of the process chamber with nitrogen.
9. The method of claim 1 wherein preconditioning the process chamber with an aggressive plasma comprises reducing a relative partial pressure of at least one of oxygen and water in the process chamber.
10. The method of claim 1 further comprising employing the aggressive plasma preconditioning step to reduce variation between sequences of nitridation steps that employ different power levels.
11. The method of claim 1 wherein preconditioning the process chamber is performed immediately before performing plasma nitridation on the substrate.
12. The method of claim 1 wherein preconditioning the process chamber is performed during an idle time of the process chamber.
13. The method of claim 1 wherein the process chamber is preconditioned using a plasma power that is at least 200% higher than a plasma power used during plasma nitridation of the substrate.
14. The method of claim 1 further comprising preconditioning the process chamber with an aggressive plasma before each substrate processed within the process chamber.
15. The method of claim 1 wherein performing plasma nitridation on the substrate comprises nitriding an oxide layer of the substrate.
16. A method comprising:
preconditioning a process chamber with a first aggressive nitrogen plasma;
loading a first substrate into the process chamber;
performing plasma nitridation on the first substrate, wherein the process chamber is preconditioned with the first aggressive nitrogen plasma using a plasma power that is at least 150% higher than a plasma power used during plasma nitridation of the first substrate;
preconditioning the process chamber with a second aggressive nitrogen plasma;
loading a second substrate into the process chamber; and
performing plasma nitridation on the second substrate, wherein the process chamber is preconditioned with the second aggressive nitrogen plasma using a plasma power that is at least 150% higher than a plasma power used during plasma nitridation of the second substrate.
17. The method of claim 16 wherein preconditioning the process chamber with the first and second aggressive plasmas comprises employing a plasma power of about 800 to 2500 watts.
18. The method of claim 16 wherein preconditioning the process chamber with the first and second aggressive plasmas comprises preconditioning the process chamber for about 5 to 60 seconds.
19. The method of claim 16 wherein preconditioning the process chamber with the first and second aggressive plasmas comprises employing a chamber pressure of about 10 to 100 milliTorr.
20. A method comprising:
preconditioning a process chamber with an aggressive plasma so as to cause nitrogen to be absorbed or adsorbed onto at least one of process kit parts and chamber walls of the process chamber;
loading a substrate into the process chamber; and
performing plasma nitridation on the substrate within the process chamber.
21. The method of claim 20 wherein preconditioning the process chamber with a nitrogen plasma comprises saturating at least one of process kit parts and chamber walls of the process chamber with nitrogen.
22. The method of claim 20 further comprising employing the aggressive plasma preconditioning step to reduce variation between sequences of nitridation steps that employ different power levels.
23. The method of claim 15 wherein the oxide layer comprises silicon dioxide.
24. The method of claim 15 wherein the oxide layer comprises a high K film.