Method for RF power distribution in a multi-zone electrode array
Embodiments of systems and methods for RF power distribution in a multi-zone electrode array are described. A system may include a plasma source configured to generate a plasma field. Also, the system may include an RF power source coupled to the plasma source and configured to supply RF power to the plasma source. The system may also include a source controller coupled to the RF power source and configured to control modulation of the RF power supplied to the plasma source to enhance uniformity of a plasma field generated by the plasma source.
1. A system for plasma processing, comprising:
a plasma source including a first electrode assembly having a first plurality of source electrodes and a second electrode assembly having a second plurality of source electrodes, the first electrode assembly and the second electrode assembly being in a facing arrangement that defines a processing region between the first electrode assembly and the second electrode assembly, the plasma source being configured to generate a plasma field in the processing region;
a first multiplexer for selectably applying Radio Frequency (RF) power to the first plurality of source electrodes in the first electrode assembly independently;
a second multiplexer for selectably applying the RF power to the second plurality of source electrodes in the second electrode assembly independently;
a first Radio Frequency (RF) power source coupled to the first electrode assembly via the first multiplexer and a second Radio Frequency (RF) power source coupled to the second electrode assembly via the second multiplexer and configured to supply the RF power to the plasma source; and
a source controller coupled to the first and second RF power sources, the first multiplexer, and the second multiplexer, and configured to control modulation of the RF power supplied to the plasma source to enhance uniformity of the plasma field generated by the plasma source by selectably applying the RF power to each of the plurality of source electrodes in at least one of the first electrode assembly and the second electrode assembly in series.
2. The system of claim 1 , wherein the number of source electrodes in the first electrode assembly is in a range of 2 to 100.
3. The system of claim 1 , wherein the first multiplexer comprises a switch for selectably applying the RF power to each of the plurality of source electrodes in the first electrode assembly independently.
4. The system of claim 1 , wherein the number of source electrodes in the second electrode assembly is in a range of 2 to 100.
5. The system of claim 1 , wherein the first RF power source is configured to apply High Frequency (HF) power to the plasma source.
6. The system of claim 1 , wherein the second RF power source is configured to apply Low Frequency (LF) power to the plasma source.
7. The system of claim 1 , wherein at least one of first and second RF power sources a configured to apply mixed- frequency power to the plasma source.
8. The system of claim 1 , wherein at least one of first and second RF power sources is configured to apply non-sinusoidal power to the plasma source, wherein at least one of the magnitude and period of the power is variable with time.
9. The system of claim 1 , wherein the source controller is configured to modulate frequency of RF power supplied to at least one of the first and second RF power sources within a specified time period, and wherein the frequency of the RF power supplied is in a range from 1 Hertz to 200 MegaHertz.
10. The system of claim 1 , wherein the source controller is configured to modulate a duty cycle of power supplied to at least one of the first and second RF power sources, and wherein a cycle time of the modulated duty cycle is in a range of 0.1 milliseconds to 10 seconds.
11. The system of claim 1 , wherein the source controller is configured to cause at least one of the first and second RF powers sources to supply a pseudo-Continuous Wave (CW) power to the plasma source.
12. The system of claim 1 , wherein the source controller is configured to cause at least one of the first and second RF power sources to supply RF power pulses to the plasma source.
13. The system of claim 1 , wherein the source controller is configured to cause at least one of the first and second RF power sources to supply a combination of pseudo-Continuous Wave (CW) power and RF power pulses to the plasma source.
14. The system of claim 1 , wherein the plasma source comprises a plurality of ring-shaped source electrodes arranged concentrically or an array of patch electrodes or an array of strip electrodes.