High voltage switching circuit

• US 9,844,127 B2
• Filed: 11/10/2015
• Issued: 12/12/2017
• Est. Priority Date: 01/10/2014
• Status: Active Grant

• Current Assignee: ASM America Incorporated (ASM International NV)
• Original Assignee: Reno Technologies Inc.
• Inventors: Bhutta, Imran
• Primary Examiner(s): Hammond, Dedei K
• Application Number:
  US14/936,978
• Publication Number:
  US 20160064161A1
• Time in Patent Office: 763 Days
• Field of Search: None
• CPC Class Codes: H03H 7/38 Impedance-matching networks
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence
• CPC Class Codes: H05H 1/4645 Radiofrequency discharges
• CPC Class Codes: H05H 2242/26 Matching networks

Abstract

A switching circuit includes: an electronic switch comprising one or more diodes for switching a capacitor within an electronic variable capacitor array; a first power switch receiving a common input signal and a first voltage input; and a second power switch receiving the common input signal and a second voltage input, wherein the second voltage input is opposite in polarity to the first voltage input, and the first power switch and the second power switch asynchronously connect the first voltage input and the second voltage input, respectively, to a common output in response to the common input signal, the one or more diodes being switched according to the first voltage input or the second voltage input connected to the common output.

Claims

1. A switching circuit comprising:

an electronic switch comprising one or more diodes for switching a capacitor within an electronic variable capacitor array (EVC);

a first power switch receiving a common input signal and a first voltage input and configured to switchably connect the first voltage input to a common output in response to the common input signal; and

a second power switch receiving the common input signal and a second voltage input and configured to switchably connect the second voltage input to the common output in response to the common input signal, wherein;

the second voltage input is opposite in polarity to the first voltage input, and

the first power switch and the second power switch are configured to asynchronously connect the first voltage input and the second voltage input, respectively, to the common output in response to the common input signal, the one or more diodes of the electronic switch being switched according to the first voltage input or the second voltage input being connected to the common output.

2. The switching circuit of claim 1, wherein the one or more diodes comprises one or more PiN diodes or one or more NiP diodes.

3. The switching circuit of claim 2, wherein each diode of the one or more diodes comprises a bare die diode directly coupled to a surface of the EVC array.

4. The switching circuit of claim 2, wherein the one or more diodes comprises a plurality of diodes coupled in series.

5. The switching circuit of claim 4, wherein the plurality of diodes comprises a plurality of bare die diodes forming a stack of diodes, each bare die diode having a cathode end and an anode end, and wherein a cathode end of a first of the bare die diodes is directly coupled to an anode end of a second of the bare die diodes.

6. The switching circuit of claim 5, wherein the stack of diodes is directly coupled to a surface of the EVC array.

7. The switching circuit of claim 1, wherein the first voltage input is greater than 1000 volts.

8. The switching circuit of claim 1, wherein the first power switch comprises a plurality of optocoupler phototransistors.

9. The switching circuit of claim 1, wherein the common input signal is a 5 volt control signal.

10. A switching circuit comprising:

an electronic switch comprising one or more diodes for switching a capacitor within an electronic variable capacitor array (EVC);

a first power switch receiving a common input signal and a first voltage input and configured to switchably connect the first voltage input to a common output in response to the common input signal; and

a second power switch receiving the common input signal and a second voltage input and configured to switchably connect the second voltage input to the common output in response to the common input signal, wherein;

the second voltage input is about three orders of magnitude or more less than the first voltage input, and

the first power switch and the second power switch are configured to asynchronously connect the first voltage input and the second voltage input, respectively, to the common output in response to the common input signal, the one or more diodes of the electronic switch being switched according to the first voltage input or the second voltage input being connected to the common output.

11. The switching circuit of claim 10, wherein the one or more diodes comprises one or more PiN diodes or one or more NiP diodes.

12. The switching circuit of claim 11, wherein each diode of the one or more diodes comprises a bare die diode directly coupled to a surface of the EVC array.

13. The switching circuit of claim 11, wherein the one or more diodes comprises a plurality of diodes coupled in series.

14. The switching circuit of claim 11, wherein the plurality of diodes comprises a plurality of bare die diodes forming a stack of diodes, each bare die diode having a cathode end and an anode end, and wherein a cathode end of a first of the bare die diodes is directly coupled to an anode end of a second of the bare die diodes.

15. The switching circuit of claim 14, wherein the stack of diodes is directly coupled to a surface of the EVC array.

16. The switching circuit of claim 10, wherein the first voltage input is greater than about 1000 volts.

17. The switching circuit of claim 10, wherein the first power switch comprises at least one optocoupler phototransistor.

18. The switching circuit of claim 10, wherein the common input signal is a 5 volt control signal.

19. An RF impedance matching network comprising:

an RF input configured to operably couple to an RF source, the RF source having a fixed RF source impedance;

an RF output configured to operably couple to a plasma chamber, the plasma chamber having a variable plasma impedance;

a series electronically variable capacitor (“

series EVC”

) having a series variable capacitance and comprising a first plurality of capacitors, the series EVC electrically coupled in series between the RF input and the RF output;

a shunt electronically variable capacitor (“

shunt EVC”

) having a shunt variable capacitance and comprising a second plurality of capacitors, the shunt EVC electrically coupled in parallel between a ground and one of the RF input and the RF output;

an inductor electrically coupled in series between the RF input and the RF output; and

a control circuit operatively coupled to the series EVC and to the shunt EVC to control the series variable capacitance and the shunt variable capacitance, wherein the control circuit is configured to;

determine the variable plasma impedance of the plasma chamber;

determine a series capacitance value for the series variable capacitance and a shunt capacitance value for the shunt variable capacitance; and

generate a control signal to alter at least one of the series variable capacitance and the shunt variable capacitance to the series capacitance value and the shunt capacitance value, respectively, the control signal comprising a common input signal;

wherein the alteration of the at least one of the series variable capacitance and the shunt variable capacitance is caused by at least one of a plurality of switching circuits, wherein each of the plurality of switching circuits is configured to switch one capacitor of the first plurality of capacitors and the second plurality of capacitors such that each of the first plurality of capacitors and the second plurality of capacitors is configured to be switched, each switching circuit comprising;

an electronic switch electrically coupled to the one capacitor, the electronic switch comprising one or more diodes for switching the one capacitor of the first plurality of capacitors and the second plurality of capacitors; and

a driver circuit having a common output electrically coupled to the electronic switch, the driver circuit comprising;

a first power switch receiving the common input signal and a first voltage and configured to switchably provide the first voltage to the common output in response to the common input signal, the first power switch comprising a plurality of optocoupler phototransistors connected in series; and

a second power switch receiving the common input signal and a second voltage and configured to switchably provide the second voltage to the common output in response to the common input signal, wherein;

the second voltage is opposite in polarity to the first voltage;

the first power switch and the second power switch are configured to asynchronously provide the first voltage and the second voltage, respectively, to the common output in response to the common input signal, the electronic switch being switched according to the first voltage or the second voltage being provided to the common output; and

when the plurality of optocoupler phototransistors of the first power switch are switched off, a voltage drop from the first voltage to the second voltage occurs across the plurality of optocoupler phototransistors.

20. The RF impedance matching network of claim 19, wherein the one or more diodes of each electronic switch comprises one or more PiN diodes or one or more NiP diodes.

21. The RF impedance matching network of claim 20, wherein each diode of the one or more diodes of each electronic switch comprises a bare die diode directly coupled to a surface of one of the series EVC and the shunt EVC.

22. The RF impedance matching network of claim 20, wherein the one or more diodes of each electronic switch comprises a plurality of diodes coupled in series.

23. The RF impedance matching network of claim 20, wherein the plurality of diodes of each electronic switch comprises a plurality of bare die diodes forming a stack of diodes, each bare die diode having a cathode end and an anode end, and wherein a cathode end of a first of the bare die diodes is directly coupled to an anode end of a second of the bare die diodes.

24. The RF impedance matching network of claim 23, wherein the stack of diodes of each electronic switch is directly coupled to a surface of one of the series EVC and the shunt EVC.

25. The RF impedance matching network of claim 19, wherein each first voltage input is greater than about 1000 volts.

26. The RF impedance matching network of claim 19, wherein each common input signal is a 5 volt control signal.

27. A method of switching a capacitor within an electronic variable capacitor array, the method comprising:

providing an electronic switch comprising one or more diodes;

receiving, at a first power switch, a common input signal and a first voltage input;

switchably connecting, by the first power switch, the first voltage input to a common output in response to the common input signal;

receiving, at a second power switch, the common input signal and a second voltage input; and

switchably connecting, by the second power switch, the second voltage input to the common output in response to the common input signal;

wherein the second voltage input is (a) opposite in polarity to the first voltage input, or (b) about three orders of magnitude or more less than the first voltage input; and

wherein the first power switch and the second power switch are configured to asynchronously connect the first voltage input and the second voltage input, respectively, to the common output in response to the common input signal, the one or more diodes of the electronic switch being switched according to the first voltage input or the second voltage input being connected to the common output.

28. The method of claim 27:

wherein the one or more diodes comprises one or more PiN diodes or one or more NiP diodes;

wherein the one or more diodes comprises a plurality of diodes coupled in series; and

wherein the plurality of diodes comprises a plurality of bare die diodes forming a stack of diodes, each bare die diode having a cathode end and an anode end, and wherein a cathode end of a first of the bare die diodes is directly coupled to an anode end of a second of the bare die diodes the one or more diodes comprises a plurality of PiN diodes or NiP diodes coupled in series.