Phase and frequency control of a radio frequency generator from an external source

• US 8,395,322 B2
• Filed: 09/23/2011
• Issued: 03/12/2013
• Est. Priority Date: 04/18/2005
• Status: Active Grant

• Current Assignee: MKS Instruments Incorporated
• Original Assignee: MKS Instruments Incorporated
• Inventors: Coumou, David J.
• Primary Examiner(s): Le, Tung X
• Application Number:
  US13/241,650
• Publication Number:
  US 20120013253A1
• Time in Patent Office: 536 Days
• Field of Search: 315/111.21, 315/111.41, 315/261, 315/326, 219/121.43, 219/121.54, 118/723.I, 118/723.R
• US Class Current: 315/111.21
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32174 Circuits specially adapted for controlling the RF discharge
• CPC Class Codes: H05B 31/26 Influencing the shape of arc discharge by gas blowing devices
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence

Abstract

A first radio frequency (RF) generator includes a first RF power source that generates an RF power output. A first sensor generates at least one sensor signal based on the RF power output. A first signal processing unit generates magnitude and phase signals associated with the at least one sensor signal. A second signal processing unit generates a first control signal to control a frequency and a phase of the first RF power source based on the magnitude and phase signals. The first RF power source determines, based on the magnitude signals, whether to generate the RF power output in response to the first control signal or in response to a second control signal received from a second RF generator.

Claims

1. A radio frequency (RF) generator comprising:

a RF power source;

a sensor coupled to the RF power source;

a sensor signal processing unit coupled to the power source and to the sensor, the sensor signal processing unit receiving a control input from an external RF generator and to generate a control signal to control at least one of phase or frequency of the RF generator.

2. The RF generator of claim 1, wherein the control input is one of a phase set point or a mix frequency set point.

3. The RF generator of claim 2, wherein the external RF generator includes a user defined input.

4. The RF generator of claim 1, wherein the sensor signal processing unit comprises a field programmable gate array (FPGA) unit and a digital signal processing unit.

5. The RF generator of claim 4, wherein the FPGA unit is operable to receive a phase and frequency input signal.

6. The RF generator of claim 4, wherein the signal processing unit is operable to generate the control signal.

7. A radio frequency (RF) generator comprising:

means for generating RF power;

sensor means coupled to the power source; and

a sensor signal processing means coupled to the means for generating RF power the sensor means, the sensor signal processing means adapted to receive an input from an external RF generator means and to generate a control signal to control at least one of phase or frequency of the RF generator.

8. A first radio frequency (RF) generator comprising:

a first RF power source that generates an RF power output;

a first sensor that generates at least one sensor signal based on the RF power output;

a first signal processing unit that generates magnitude and phase signals associated with the at least one sensor signal; and

a second signal processing unit that generates a first control signal to control a frequency and a phase of the first RF power source based on the magnitude and phase signals,

wherein the first RF power source determines, based on the magnitude signals, whether to generate the RF power output in response to the first control signal or in response to a second control signal received from a second RF generator.

9. The first RF generator of claim 8 wherein the first signal processing unit generates the magnitude and phase signals based on setpoint information.

10. The first RF generator of claim 9 wherein the first signal processing unit generates the magnitude and phase signals according to a frequency of interest indicated in the setpoint information.

11. The first RF generator of claim 9 wherein the setpoint information includes at least one of a power level, a frequency offset, and a phase offset.

12. The first RF generator of claim 9 wherein the second signal processing unit generates the setpoint information.

13. The first RF generator of claim 8 wherein the at least one sensor signal corresponds to at least one of:

a voltage and a current of the RF power output; and

a forward and reverse characteristic of the RF power output.

14. The first RF generator of claim 8 wherein the magnitude signals correspond to at least one of a magnitude of a voltage and a magnitude of a current.

15. The first RF generator of claim 8 wherein the first RF power source determines whether to generate the RF power output in response to the first control signal or in response to the second control signal based on a comparison between at least one of the magnitude signals and a threshold.

16. The first RF generator of claim 8 wherein the second control signal is based on a user defined input.

17. A method for operating a first radio frequency (RF) generator, the method comprising:

generating an RF power output using a first RF power source;

generating at least one sensor signal based on the RF power output;

generating magnitude and phase signals associated with the at least one sensor signal;

generating a first control signal to control a frequency and a phase of the first RF power source based on the magnitude and phase signals; and

determining, based on the magnitude signals, whether to generate the RF power output in response to the first control signal or in response to a second control signal received from a second RF generator.

18. The method of claim 17 further comprising generating the magnitude and phase signals based on setpoint information.

19. The method of claim 18 further comprising generating the magnitude and phase signals according to a frequency of interest indicated in the setpoint information.

20. The method of claim 18 wherein the setpoint information includes at least one of a power level, a frequency offset, and a phase offset.

21. The method of claim 17 wherein the at least one sensor signal corresponds to at least one of:

a voltage and a current of the RF power output; and

a forward and reverse characteristic of the RF power output.

22. The method of claim 17 wherein the magnitude signals correspond to at least one of a magnitude of a voltage and a magnitude of a current.

23. The method of claim 17 further comprising determining whether to generate the RF power output in response to the first control signal or in response to the second control signal based on a comparison between at least one of the magnitude signals and a threshold.

24. The method of claim 17 wherein the second control signal is based on a user defined input.

25. The method of 17 comprising:

configuring the first RF generator as a slave RF generator; and

configuring the second RF generator as a master RF generator.