Substrate processing method and substrate processing apparatus

• US 8,821,744 B2
• Filed: 03/18/2011
• Issued: 09/02/2014
• Est. Priority Date: 09/30/2010
• Status: Active Grant

• Current Assignee: Kioxia Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Ui, Akio, Hayashi, Hisataka
• Primary Examiner(s): Vinh, Lan
• Assistant Examiner(s): Lu, Jiong-Ping
• Application Number:
  US13/051,771
• Publication Number:
  US 20120080408A1
• Time in Patent Office: 1,264 Days
• Field of Search: None
• US Class Current: 216/71
• 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 37/32146 Amplitude modulation, includes pulsing
• CPC Class Codes: H01J 37/32174 Circuits specially adapted for controlling the RF discharge
• CPC Class Codes: H01L 21/31116 by dry-etching

Abstract

A substrate processing method using a substrate processing apparatus includes a first step and a second step. The first step is to apply a negative voltage pulse from a pulsed power supply to be included in the apparatus. The second step is to apply floating potential for an interval of time between the negative voltage pulse and a positive voltage pulse from the pulsed power supply subsequent to the negative voltage pulse. In addition, the apparatus includes a chamber, a first electrode, a second electrode, an RF power supply, and the pulsed power supply. The second electrode is provided so that the second electrode faces the first electrode to hold a substrate. The RF power supply applies an RF voltage having a frequency of 50 MHz or higher to the second electrode. The pulsed power supply repeatedly applies a voltage waveform with the RF voltage to the second electrode.

Claims

1. A substrate processing method using a substrate processing apparatus, comprising:

a first step of applying a negative voltage pulse from a pulsed power supply included in the apparatus; and

a second step of applying a floating potential for an interval of time between the negative voltage pulse and a positive voltage pulse from the pulsed power supply subsequent to the negative voltage pulse,

wherein the apparatus includes;

a chamber;

a first electrode provided inside the chamber;

a second electrode provided inside the chamber so that the second electrode faces the first electrode and to hold a substrate;

an RF power supply to apply an RF voltage having a frequency of 50 MHz or higher to the second electrode; and

the pulsed power supply to repeatedly apply a voltage waveform with the RF voltage to the second electrode, the voltage waveform including a negative voltage pulse and a positive voltage pulse, the pulsed power supply including a first power supply to output a first voltage corresponding to a peak voltage of the negative voltage pulse, a second power supply to output a second voltage corresponding to a peak voltage of the positive voltage pulse, a ground terminal to provide a ground potential, and an output terminal to which any one of the first power supply, the second power supply, and the ground terminal is applied, and the floating potential being applied to the second electrode between applying the negative voltage pulse and the positive voltage pulse by disconnecting the output terminal of the pulsed power supply from the first power supply, the second power supply, and the ground terminal.

2. The substrate processing method according to claim 1, further comprising:

applying a ground potential for an interval of time between the positive voltage pulse and the negative voltage pulse subsequent to the positive voltage pulse, both the negative pulse voltage and the positive pulse voltage being outputted by the pulsed power supply.

3. The substrate processing method according to claim 1, wherein an interval of time to output the floating potential is 50 ns or shorter.

4. A substrate processing method using a substrate processing apparatus, comprising:

a first step of applying a negative voltage pulse from a pulsed power supply included in the apparatus; and

a second step of applying a floating potential for an interval of time between the negative voltage pulse and a positive voltage pulse from the pulsed power supply subsequent to the negative voltage pulse;

wherein the apparatus includes;

a chamber;

a first electrode provided inside the chamber;

a second electrode provided inside the chamber so that the second electrode faces the first electrode and to hold a substrate;

an RF power supply to apply an RF voltage having a frequency of 50 MHz or higher to the second electrode; and

the pulsed power supply to repeatedly apply a voltage waveform with the RF voltage to the second electrode, the voltage waveform including the negative voltage pulse and the positive voltage pulse;

wherein under a state of applying the floating potential from the pulsed power supply, an output terminal of the pulsed power supply is opened to block off a current from and to the second electrode.

5. The substrate processing method according to claim 4, further comprising:

applying a ground potential for an interval of time between the positive voltage pulse and the negative voltage pulse subsequent to the positive voltage pulse, both the negative voltage pulse and the positive voltage pulse being outputted by the pulsed power supply.

6. The substrate processing method according to claim 4, wherein an interval of time to output the floating potential is 50 ns or shorter.

7. A substrate processing method using a substrate processing apparatus, comprising:

a first step of applying a negative voltage pulse from a pulsed power supply included in the apparatus; and

a second step of applying a floating potential for an interval of time between the negative voltage pulse and a positive voltage pulse from the pulsed power supply subsequent to the negative voltage pulse;

wherein the apparatus includes;

a chamber;

a first electrode provided inside the chamber;

a second electrode provided inside the chamber so that the second electrode faces the first electrode and to hold a substrate;

an RF power supply to apply an RF voltage having a frequency of 50 MHz or higher to the second electrode; and

the pulsed power supply to repeatedly apply a voltage waveform with the RF voltage to the second electrode, the voltage waveform including the negative voltage pulse and the positive voltage pulse;

wherein the pulsed power supply includes a first power supply to output a first voltage, a second power supply to output a second voltage, and a switching unit configured to switch off the first power supply and the second power supply to block off the first voltage and the second voltage applied to the second electrode so that the floating potential is applied.

8. The substrate processing method according to claim 7, further comprising:

applying a ground potential for an interval of time between the positive voltage pulse and the negative voltage pulse subsequent to the positive voltage pulse, both the negative voltage pulse and the positive voltage pulse being outputted by the pulsed power supply.

9. The substrate processing method according to claim 7, wherein an interval of time to output the floating potential is 50 ns or shorter.