Granted Patent B2

US 12,476,084 · App. 18/274,808 · Granted Nov 18, 2025

Inventors: Masaharu Shiratani (Fukuoka, JP); Kunihiro Kamataki (Fukuoka, JP); Kazunori Koga (Fukuoka, JP); Takahiro Shindo (Nirasaki, JP); Tatsuo Matsudo (Nirasaki, JP)

Assignees: Tokyo Electron Limited; Kyushu University, National University Corporation

H01J37/32183H03H11/44H01J2237/332H01J2237/334

Abstract

Claims (37)

1 . A plasma processing apparatus for performing plasma processing on a substrate, comprising:

a processing container accommodating the substrate;

an electrode to which a high-frequency power for generating plasma in the processing container is applied;

a high-frequency power supply configured to apply the high-frequency power to the electrode; and

a high-frequency power supply circuit configured to supply the high-frequency power from the high-frequency power supply to the electrode,

wherein the high-frequency power supply circuit comprises:

a power supply path configured to supply a power from the high-frequency power supply to the electrode; and

a matching device configured to match a high-frequency power supply-side impedance with a plasma-side impedance, the matching device comprising a negative impedance portion that is connected to the power supply path and realizes a negative impedance corresponding to a plasma-side impedance.

2 . The plasma processing apparatus of claim 1 , wherein the negative impedance portion is formed of a negative impedance conversion circuit or a metamaterial.

3 . The plasma processing apparatus of claim 2 , wherein the negative impedance conversion circuit has an operational amplifier.

4 . The plasma processing apparatus of claim 3 , wherein an output stage of the operational amplifier has a plurality of transistors for outputting a voltage at which the plasma is ignited.

5 . The plasma processing apparatus of claim 3 , wherein the negative impedance conversion circuit further comprises:

a booster circuit disposed at a subsequent stage of the operational amplifier and configured to output a voltage at which the plasma is ignited.

6 . The plasma processing apparatus of claim 1 , wherein the matching device comprises a plurality of the negative impedance portions.

7 . The plasma processing apparatus of claim 6 , wherein the high-frequency power supply circuit further comprises:

a combiner configured to combine outputs of the plurality of negative impedance portions.

8 . The plasma processing apparatus of claim 1 , wherein the high-frequency power supply circuit further comprises:

a booster configured to boost an output of the negative impedance portion or an amplifier configured to amplify an output of the negative impedance portion.

9 . The plasma processing apparatus of claim 1 , wherein the matching device further comprises:

an impedance adjustment part connected to the negative impedance portion and configured to adjust an impedance of the matching device.

10 . The plasma processing apparatus of claim 9 , wherein the impedance adjustment part has a variable reactance circuit having a variable capacitor and/or a variable coil.

11 . The plasma processing apparatus of claim 9 , wherein the impedance adjustment part has a plasma generation part configured to generate plasma using a same recipe as used when the plasma is generated in the processing container.

12 . The plasma processing apparatus of claim 9 , wherein the impedance adjustment part has an impedance mirroring circuit having an active element and is configured to adjust an impedance to realize a same impedance as the impedance of the plasma in the processing container.

13 . A high-frequency power supply circuit that supplies a high-frequency power to an electrode for generating plasma from a high-frequency power supply, comprising:

a power supply path that supplies a power from the high-frequency power supply to the electrode; and

a matching device that comprises a negative impedance portion connected to the power supply path and configured to realize a negative impedance corresponding to a plasma-side impedance, and matches a high-frequency power supply-side impedance with the plasma-side impedance.

14 . The high-frequency power supply circuit of claim 13 , wherein the negative impedance portion is a negative impedance conversion circuit or a metamaterial having a negative impedance.

15 . The high-frequency power supply circuit of claim 14 , wherein the negative impedance conversion circuit has an operational amplifier.

16 . The plasma processing apparatus of claim 13 , wherein the matching device has a plurality of negative impedance portions.

17 . The high-frequency power supply circuit of claim 13 , further comprising:

a booster configured to boost an output of the negative impedance portion or an amplifier configured to amplify an output of the negative impedance portion.

18 . The high-frequency power supply circuit of claim 13 , wherein the matching device further comprises:

an impedance adjustment part connected to the negative impedance portion and configured to adjust an impedance of the matching device.

19 . An impedance matching method performed when plasma is generated by supplying a high-frequency power, comprising:

supplying a high-frequency power for plasma generation from a high-frequency power supply to an electrode through a power supply path; and

matching a high-frequency power supply-side plasma with a plasma-side impedance using a matching device comprising a negative impedance portion connected to the power supply path and configured to realize a negative impedance corresponding to the plasma-side impedance.

20 . The impedance matching method of claim 19 , wherein the negative impedance portion is formed of a negative impedance conversion circuit or a metamaterial having a negative impedance.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (20)