RF power delivery with approximated saw tooth wave pulsing

Patent metadata

Field	Value
Publication number	US-9788405-B2
Application number	US-201514882878-A
Country	US
Kind code	B2
Filing date	Oct 14, 2015
Priority date	Oct 3, 2015
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

Methods of operating a plasma enhanced substrate processing system using multi-level pulsed RF power are provided herein. In some embodiments, a method of operating a plasma enhanced substrate processing system using multi-level pulsed RF power includes providing a first multi-level RF power waveform to a process chamber, the first multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, and providing, after a first delay period, a second multi-level RF power waveform to the process chamber, the second multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration.

First claim

The invention claimed is:

1. A method of operating a plasma enhanced substrate processing system using multi-level pulsed RF power, comprising:
providing, from a first RF generator to a ceiling of a process chamber, a first multi-level RF power waveform to the process chamber, the first multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the first multi-level RF power waveform are different from each other;
providing, from a second RF generator to a substrate support included in the process chamber and after a first delay period, a second multi-level RF power waveform to the process chamber, the second multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the second multi-level RF power waveform are different from each other; and
providing, from a third RF generator to the substrate support included in the process chamber and after a second delay period, a third multi-level RF power waveform to the process chamber, the third multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the third multi-level RF power waveform are different from each other.

2. The method of claim 1 , wherein the first multi-level RF power waveform and the second multi-level RF power waveform are synchronized.

3. The method of claim 1 , wherein the first power level of the first multi-level RF power waveform is a high power level, the second power level of the first multi-level RF power waveform is a low power level that is lower than the first power level of the first multi-level RF power waveform, and the third power level of the first multi-level RF power waveform is a zero power level.

4. The method of claim 3 , wherein the first power level of the second multi-level RF power waveform is a high power level, the second power level of the second multi-level RF power waveform is a low power level that is lower than the first power level of the second multi-level RF power waveform, and the third power level of the second multi-level RF power waveform is a zero power level.

5. The method of claim 1 , wherein the first multi-level RF power waveform and the third multi-level RF power waveform are synchronized.

6. The method of claim 1 , wherein the first multi-level RF power waveform, the second multi-level RF power waveform, and the third multi-level RF power waveform are synchronized.

7. The method of claim 1 , wherein one of the first, second and third power levels of each of the first, second, and third multi-level RF power waveforms is a zero power level.

8. The method of claim 1 , wherein a duration of time that each of the first, second and third power levels of the first multi-level RF power waveform are applied are different from each other.

9. The method of claim 1 , wherein a duration of time that each of the first, second and third power levels of the second multi-level RF power waveform are applied are different from each other.

10. The method of claim 1 , wherein a duration of time that each of the first, second and third power levels of the third multi-level RF power waveform are applied are different from each other.

11. The method of claim 1 , wherein first multi-level RF power waveform is a source RF signal, and the second and third multi-level RF power waveforms are RF bias signals.

12. The method of claim 1 , wherein the first delay period is between about 10 μs to about 1 ms.

13. The method of claim 1 , wherein the second delay period is between about 10 μs to about 1 ms.

14. A non-transitory computer readable medium having instructions stored thereon that, when executed, cause a method of operating a plasma enhanced substrate processing system using multi-level pulsed RF power to be performed, the method comprising:
providing, from a first RF generator to a ceiling of a process chamber, a first multi-level RF power waveform to the process chamber, the first multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the first multi-level RF power waveform are different from each other;
providing, from a second RF generator to a substrate support included in the process chamber and after a first delay period, a second multi-level RF power waveform to the process chamber, the second multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the second multi-level RF power waveform are different from each other; and
providing, from a third RF generator to the substrate support included in the process chamber and after a second delay period, a third multi-level RF power waveform to the process chamber, the third multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the third multi-level RF power waveform are different from each other.

15. The non-transitory computer readable medium of claim 14 , wherein one of the first, second and third power levels of each of the first, second, and third multi-level RF power waveforms is a zero power level.

16. A plasma enhanced substrate processing system comprising:
a first RF generator configured to provide a first multi-level RF power waveform to a ceiling of a process chamber, the first multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the first multi-level RF power waveform are different from each other;
a second RF generator configured to provide, after a first delay period, a second multi-level RF power waveform to a substrate support included in the process chamber, the second multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the second multi-level RF power waveform are different from each other; and
a third RF generator configured to provide, after a second delay period, a third multi-level RF power waveform to the substrate support included in the process chamber, the third multi-level RF power waveform having at least a first power level during a first pulse duration, a second power level during a second pulse duration, and a third power level during a third pulse duration, wherein the first, second and third power levels of the third multi-level RF power waveform are different from each other.

17. The plasma enhanced substrate processing system of claim 16 , w

Assignees

• Applied Materials Inc

Inventors

• Kawasaki Katsumasa
• Shoji Sergio Fukuda
• Phi Justin
• Shimizu Daisuke

Classifications

• H10P50/242

  of Group IV materials · CPC title

• H03K4/08

  having sawtooth shape · CPC title

• H05H1/46 Primary

  using applied electromagnetic fields, e.g. high frequency or microwave energy (H05H1/26 takes precedence) · CPC title

• H01J37/32174 Primary

  Circuits specially adapted for controlling the RF discharge · CPC title

• H01J37/32183

  Matching circuits · CPC title