Adjustable Capacitor, Plasma Impedance Matching Device, Plasma Impedance Matching Method, And Substrate Treating Apparatus

• US 20120168081A1
• Filed: 12/27/2011
• Published: 07/05/2012
• Est. Priority Date: 12/30/2010
• Status: Active Grant

• Current Assignee: Semes Co., Ltd (Samsung Electronics Co. Ltd.)
• Original Assignee: Semes Co., Ltd (Samsung Electronics Co. Ltd.)
• Inventors: Son, Dukhyun
• Granted Patent: US 9,715,996 B2
• Time in Patent Office: Days
• US Class Current: 156/345.28
• CPC Class Codes: H01G 5/16 using variation of distance between electrodes
• CPC Class Codes: H01J 37/32091 the radio frequency energy being capacitively coupled to the plasma
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32174 Circuits specially adapted for controlling the RF discharge
• CPC Class Codes: H01J 37/32183 Matching circuits
• 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 2242/26 Matching networks

Abstract

Disclosed is a substrate treating apparatus which comprises a process chamber; an electrode configured to generate plasma from a gas supplied into the process chamber; an RF power supply configured to output an RF power; a transmission line configured to transmit the RF power to the electrode from the RF power supply; an impedance matching unit connected to the transmission line and configured to match plasma impedance; and a controller configured to output a control signal to the impedance matching unit, wherein the impedance matching unit comprises an adjustable capacitor having a plurality of capacitors and a plurality of switches corresponding to the plurality of capacitors, the plurality of switches being switched on/off according to the control signal so that capacitance of the adjustable capacitor is adjusted.

Claims

1. A substrate treating apparatus comprising:

a process chamber;

an electrode configured to generate plasma from a gas supplied into the process chamber;

an RF power supply configured to output an RF power;

a transmission line configured to transmit the RF power to the electrode from the RF power supply;

an impedance matching unit connected to the transmission line and configured to match plasma impedance; and

a controller configured to output a control signal to the impedance matching unit,

wherein the impedance matching unit comprises an adjustable capacitor having a plurality of capacitors and a plurality of switches corresponding to the plurality of capacitors, the plurality of switches being switched on/off according to the control signal so that capacitance of the adjustable capacitor is adjusted.

2. The substrate treating apparatus of claim 1, wherein the plurality of capacitors is grouped into N groups (N being an integer bigger than 1), and capacitance ranges adjusted by the respective groups are different.

3. The substrate treating apparatus of claim 2, wherein each group includes a plurality of capacitors.

4. The substrate treating apparatus of claim 3, wherein the groups are connected in parallel.

5. The substrate treating apparatus of claim 4, wherein a plurality of capacitors in each group is connected in parallel.

6. The substrate treating apparatus of claim 5, wherein capacitors in the same group haves the same capacitance.

7. The substrate treating apparatus of claim 6, wherein each group includes nine capacitors.

8. The substrate treating apparatus of claim 7, wherein a capacitance ratio of the N groups is 10⁰:

10¹;

10²;

10³ . . . ;

10^n-1.

9. The substrate treating apparatus of claim 1, wherein the RF power supply supplies the RF power in a pulse mode.

10. The substrate treating apparatus of claim 9, wherein the transmission line comprises a first transmission line connecting the adjustable capacitor and the process chamber;

and a second transmission line being diverged from the first transmission line to a ground;

wherein the substrate treating apparatus further comprises a first transmission switch provided on the first transmission line; and

a second transmission switch provided on the second transmission line; and

wherein the controller outputs an on/off signal to the first transmission switch and the second transmission switch according to a pulse mode of the RF power supply.

11. The substrate treating apparatus of claim 10, wherein the first transmission switch is located after a connection node between the first transmission line and the second transmission line.

12. A plasma impedance matching device comprising:

an impedance matching unit connected to a transmission line of an RF power and configured to match plasma impedance; and

a controller configured to send a control signal to the impedance matching unit,

wherein the impedance matching unit comprises an adjustable capacitor having a plurality of capacitors and a plurality of switches corresponding to the plurality of capacitors, the plurality of switches being switched on/off according to the control signal so that capacitance of the adjustable capacitor is adjusted.

13. The plasma impedance matching device of claim 12, wherein the plurality of capacitors is grouped into N groups (N being an integer bigger than 1), and capacitance ranges adjusted by the respective groups are different.

14. The plasma impedance matching device of claim 13, wherein each group includes a plurality of capacitors.

15. The plasma impedance matching device of claim 14, wherein the groups are connected in parallel.

16. The plasma impedance matching device of claim 15, wherein a plurality of capacitors in each group is connected in parallel.

17. The plasma impedance matching device of claim 16, wherein capacitors in the same group haves the same capacitance.

18. The plasma impedance matching device of claim 17, wherein each group includes nine capacitors.

19. The plasma impedance matching device of claim 18, wherein the switches are formed of a PIN diode.

20. The plasma impedance matching device of claim 12, wherein the plurality of capacitors is connected in parallel.

21. The plasma impedance matching device of claim 12, wherein the adjustable capacitor further comprises:

a mechanical adjustable capacitor configured to receive the control signal of the controller to adjust capacitance by a mechanical driving means.

22. An adjustable capacitor comprising:

a plurality of capacitors grouped into N groups (N being an integer bigger than

     1); and

a plurality of switches respectively connected to the plurality of capacitors and controlled according to a control signal,

wherein capacitance ranges adjusted by the respective groups are different.

23. The adjustable capacitor of claim 22, wherein each group includes a plurality of capacitors.

24. The adjustable capacitor of claim 23, wherein the groups are connected in parallel.

25. The adjustable capacitor of claim 24, wherein a plurality of capacitors in each group is connected in parallel.

26. The adjustable capacitor of claim 25, wherein capacitors in the same group haves the same capacitance.

27. The adjustable capacitor of claim 25, wherein capacitors in different groups have different capacitances.

28. The adjustable capacitor of claim 26, wherein each group includes nine capacitors.

29. The adjustable capacitor of claim 28, wherein a capacitance ratio of the N groups is 10⁰:

10¹;

10²;

10³ . . . ;

10^n-1.

30. The adjustable capacitor of claim 29, wherein the switches are formed of a PIN diode.