# US 12,603,258 B2 · Plasma processing apparatus and plasma processing method

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- Number: US 12,603,258 B2
- Document ID: US12603258B2
- Status: Granted
- Kind: B2
- Application number: 18/136,692
- Filed: 2023-04-19
- Published: 2023-08-17
- Granted: 2026-04-14
- Earliest claimed: 2020-07-16
- Assignees: Tokyo Electron Limited
- Applicants: Tokyo Electron Limited
- Inventors: Natsumi Torii; Koichi Nagami
- Web page: https://patentgrep.com/patent/US12603258B2

## CPC

- H01J 37/32146: {Amplitude modulation, includes pulsing}
- H01J 37/32715: {Workpiece holder}
- H01J 37/32091: {the radio frequency energy being capacitively coupled to the plasma}
- H01J 37/32183: {Matching circuits}
- H01J 37/32642: {Focus rings}
- H01J 37/32935: {Monitoring and controlling tubes by information coming from the object and/or discharge}
- H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H)

## Abstract

A plasma processing apparatus includes: a chamber; a substrate support disposed in the chamber, the substrate support including a lower electrode; an edge ring disposed to surround a substrate on the substrate support; an upper electrode disposed above the substrate support; a first RF power supply; a first DC power supply; and a controller configured to cause: (a) starting supply of a first RF power from the first RF power supply to the upper electrode or the lower electrode; and (b) after (a), starting the application of a first DC voltage from the first DC power supply to the edge ring when a first delay time elapses.

## Claims

### Claim 1

A plasma processing apparatus comprising:
a chamber;
a substrate support disposed in the chamber, the substrate support including a lower electrode;
an edge ring disposed on the substrate support to radially surround a substrate on an upper surface of the substrate support;
an upper electrode disposed above the substrate support;
a first RF power supply;
a switching unit including a DC power supply circuit and a charge removal circuit, the switching unit switching between the DC power supply circuit and the charge removal circuit;
a first DC power supply electrically connected to the edge ring via the switching unit; and
controller circuitry configured to cause:
(a) starting supply of a first RF power from the first RF power supply to the upper electrode or the lower electrode;
(b) after (a), starting the application of a first DC voltage from the first DC power supply to the edge ring when a first delay time elapses;
(c) after (b), controlling the first DC power supply to stop the supply of the first RF power and the application of the first DC voltage; and
(d) after (c), controlling the charge removal circuit to start charge removal of the edge ring when a second delay time elapses.

### Claim 2 (depends on 1)

The plasma processing apparatus according to claim 1, wherein the first delay time is equal to or longer than a reflection time of the first RF power.

### Claim 3 (depends on 1)

The plasma processing apparatus according to claim 1, wherein the first delay time is 0.1 μs to 1000 μs.

### Claim 4 (depends on 1)

The plasma processing apparatus according to claim 1, wherein the first delay time is 0.1 μs to 100 μs.

### Claim 5 (depends on 1)

The plasma processing apparatus according to claim 1, wherein the first delay time is 1 μs to 300 μs.

### Claim 6 (depends on 1)

The plasma processing apparatus according to claim 1, wherein the second delay time is 0.1 μs to 1000 μs.

### Claim 7 (depends on 1)

The plasma processing apparatus according to claim 1, further comprising: a second DC power supply configured to apply a second DC voltage to the edge ring after stopping the application of the first DC voltage, the second DC voltage being different from the first DC voltage.

### Claim 8 (depends on 1)

The plasma processing apparatus according to claim 1, further comprising: a second RF power supply configured to supply a second RF power to the lower electrode during (a), the second RF power being different from the first RF power.

### Claim 9 (depends on 1)

The plasma processing apparatus according to claim 1, wherein the edge ring is made of a conductive material.

### Claim 10 (depends on 1)

The plasma processing apparatus according to claim 1, further comprising:
a second RF filter, wherein
the first DC power supply is electrically connected to the edge ring via the switching unit, then the second RF filter, and then the first RF filter.

### Claim 11 (depends on 1)

The plasma processing apparatus according to claim 1, wherein the DC power supply circuit includes:
a first switching element; and
a first damping element,
the first switching element is one of a field effect transistor (FET), an insulated gate bipolar transistor (IGBT) or a relay, and
the first damping element is a resistor or a coil.

### Claim 12 (depends on 11)

The plasma processing apparatus according to claim 11, wherein the charge removal circuit includes:
a second switching element; and
a second damping element,
the second switching element is one of a field effect transistor (FET), an insulated gate bipolar transistor (IGBT) or a relay, and
the second damping element is a resistor or a coil.