Substrate processing method and substrate processing apparatus

Patent metadata

Field	Value
Publication number	US-2023386787-A1
Application number	US-202118032786-A
Country	US
Kind code	A1
Filing date	Oct 5, 2021
Priority date	Oct 19, 2020
Publication date	Nov 30, 2023
Grant date	—

Abstract

A substrate processing method for a substrate processing device includes (a) supplying a process gas with specific conditions to a processing container having therein a stage on which a workpiece having an etching target film and a mask on the etching target film is placed, (b) performing a plasma processing on the workpiece with first plasma generated from the process gas under a first plasma generation condition, (c) performing a plasma processing on the workpiece with second plasma generated from the process gas under a second plasma generation condition that is different from the first plasma generation condition in a radio-frequency power condition and a processing time, and is the same as the first plasma generation condition in other conditions, and (d) repeating (b) and (c).

First claim

1 . A substrate processing method for a substrate processing apparatus, the method comprising:
(a) supplying a process gas with a specific condition, to a processing container having therein a stage on which a workpiece having an etching target film and a mask on the etching target film is placed; (b) performing a plasma processing on the workpiece with first plasma generated from the process gas under a first plasma generation condition; (c) performing a plasma processing on the workpiece with second plasma generated from the process gas under a second plasma generation condition that is different from the first plasma generation condition in a radio-frequency condition and a processing time, and is same as the first plasma generation condition in other conditions; and (d) repeating (b) and (c).

2 . The substrate processing method according to claim 1 , wherein the second plasma is in a state where a dissociation degree of the process gas is higher than that of the first plasma.

3 . The substrate processing method according to claim 1 , wherein, in (b), a protective film is formed on the workpiece by a reaction product generated by the first plasma, and
in (c), the etching target film is etched by an etchant generated by the second plasma.

4 . The substrate processing method according to claim 1 , wherein the second plasma generation condition is a condition in which a bias potential is generated on the workpiece.

5 . The substrate processing method according to claim 1 , further comprising:
(e) performing a processing in which no plasma is generated, wherein (d) repeats (b), (c), and (e) in an order of (b), (c), and (e).

6 . The substrate processing method according to claim 5 , wherein a condition of the process gas introduced in (e) is same as conditions of the process gas introduced in (b) and (c).

7 . The substrate processing method according to claim 1 , wherein the etching target film is a silicon film,
the mask is a silicon-containing film, and the process gas includes fluorocarbon gas or hydrofluorocarbon gas.

8 . The substrate processing method according to claim 7 , wherein the process gas further includes a halogen-containing gas.

9 . The substrate processing method according to claim 8 , wherein the halogen-containing gas does not contain carbon.

10 . The substrate processing method according to claim 1 , wherein the process gas includes:
a first gas capable of generating a precursor that forms a deposit on the workpiece by being dissociated by plasma, and a second gas capable of generating a precursor that etches the etching target film by being dissociated by the plasma.

11 . The substrate processing method according to claim 1 , wherein the first plasma is capacitively coupled plasma, and
the second plasma is inductively coupled plasma.

12 . The substrate processing method according to claim 1 , wherein the first plasma is capacitively coupled plasma, and
the second plasma is microwave plasma.

13 . The substrate processing method according to claim 1 , wherein the first plasma and the second plasma are inductively coupled plasma or capacitively coupled plasma, and
a frequency of the radio-frequency power in the second plasma generation condition is higher than a frequency of the radio-frequency power in the first plasma generation condition.

14 . The substrate processing method according to claim 1 , wherein the first plasma and the second plasma are inductively coupled plasma or capacitively coupled plasma, and
an applied power of a radio-frequency power in the second plasma generation condition is higher than an applied power of the radio-frequency power in the first plasma generation condition.

15 . The substrate processing method according to claim 14 , wherein the first plasma generation condition includes changing the applied power over time as the radio-frequency power condition.

16 . The substrate processing method according to claim 1 , wherein the radio-frequency power condition and the processing time in the first and second plasma generation conditions are adjusted according to a depth of the etching target film that is etched.

17 . The substrate processing method according to claim 1 , further comprising:
(f) performing a plasma processing on the workpiece with third plasma generated from the process gas under a third plasma generation condition that is different from the first and second plasma generation conditions in the radio-frequency condition and the processing time, and is same as the first and second plasma generation conditions in other conditions, wherein (f) is performed immediately before and/or immediately after (b).

18 . The substrate processing method according to claim 17 , wherein the third plasma is in a state where a dissociation degree of the process gas is higher than that of the first plasma and lower than that of the second plasma.

19 . The substrate processing method according to claim 17 , wherein, in (f), a protective film is formed on the workpiece by a reaction product generated by the third plasma.

20 . The substrate processing method according to claim 19 , wherein the protective film is formed on a top surface of the mask by the reaction product generated by the first plasma, and
the protective film is formed on a side surface of the mask and a side surface of the etching target film that is etched, by the reaction product generated by the third plasma.

21 . The substrate processing method according to claim 18 , wherein the third plasma is inductively coupled plasma or capacitively coupled plasma, and
a frequency of the radio-frequency power in the third plasma generation condition is higher than a frequency of the radio-frequency power in the first plasma generation condition and lower than a frequency of the radio-frequency power in the second plasma generation condition.

22 . The substrate processing method according to claim 18 , wherein the third plasma is inductively coupled plasma or capacitively coupled plasma, and
an applied power of a radio-frequency power in the third plasma generation condition is higher than an applied power of the radio-frequency power in the first plasma generation condition and lower than an applied power of the radio-frequency power in the second plasma generation condition.

23 . The substrate processing method according to claim 18 , wherein the radio-frequency power condition and the processing time in the first, second, and third plasma generation conditions are adjusted according to a depth of the etching target film that is etched.

24 . The substrate processing method according to claim 22 , wherein the first and third plasma generation conditions include changing the applied power over time as the radio-frequency power condition.

25 . A substrate processing apparatus comprising:
a processing container; a stage disposed in the processing container and configured to place thereon a workpiece having an etching target film and a mask on the etching target film; and a controller, wherein (a) the controller is configured to control the substrate processing apparatus to supply a process gas with a specific condition, to the processing container; (b) the controller is configured to control the substrate processing apparatus to perform a plasma processing on the workpiece with first plasma generated from the process gas under a first plasma generation c

Assignees

• Tokyo Electron Ltd

Inventors

• Inokuchi Atsutoshi
• Saito Yasuhiko
• Maeda Kiyoshi

Classifications

• H10P50/691

  for Group V materials or Group III-V materials · CPC title

• H10P50/242 Primary

  of Group IV materials · CPC title

• H10P50/695

  characterised by the process involved to create the mask, e.g. lift-off masks or sidewalls or to modify the mask · CPC title

• H10P50/244 Primary

  comprising alternated and repeated etching and passivation steps · CPC title

• H10P50/267

  using plasmas · CPC title