Substrate processing method and substrate processing apparatus

Patent metadata

Field	Value
Publication number	US-11315795-B2
Application number	US-202117223213-A
Country	US
Kind code	B2
Filing date	Apr 6, 2021
Priority date	Apr 7, 2020
Publication date	Apr 26, 2022
Grant date	Apr 26, 2022

Abstract

A substrate processing method performed in a substrate processing apparatus includes providing a substrate which has a first film composed of silicon only and a second film including silicon; and etching the first film by plasma formed from a mixed gas including a halogen-containing gas and a silicon-containing gas but not including an oxygen-containing gas.

First claim

We claim:

1. A substrate processing method performed in a substrate processing apparatus, comprising:
providing a substrate which has a Si film, a SiN film and a SiO 2 film; and
etching the Si film by plasma formed from a mixed gas composed of a halogen-containing gas, a silicon-containing gas and a rare gas,
wherein the mixed gas does not include carbon,
the Si film and the SiN film are formed on the SiO 2 film,
top surfaces of the Si film and the SiN film are higher than a top surface of the SiO 2 film, and
the SiN film is formed to be in contact with a side surface of the Si film, and the Si film, the SiN film and the SiO 2 film are exposed to a plasma processing space.

2. A substrate processing method performed in a substrate processing apparatus, comprising:
providing a substrate which has a first film composed of silicon only and a second film including silicon; and
etching the first film by plasma formed from a mixed gas including a halogen-containing gas and a silicon-containing gas but not including an oxygen-containing gas.

3. The substrate processing method of claim 2 ,
wherein the second film includes one or more of oxygen, nitrogen and carbon.

4. The substrate processing method of claim 3 ,
wherein the second film is SiO 2 , SiN, SiC, SiON, or SiOCH 3 .

5. The substrate processing method of claim 2 ,
wherein the first film is polysilicon, amorphous silicon or single crystalline silicon.

6. The substrate processing method of claim 2 ,
wherein the substrate further has a third film including silicon.

7. The substrate processing method of claim 6 ,
wherein the first film and the second film are formed on the third film,
top surfaces of the first film and the second film are higher than a top surface of the third film, and
the second film is formed to be in contact with a side surface of the first film, and the first film to the third film are exposed to a plasma processing space.

8. The substrate processing method of claim 7 ,
wherein the third film and the second film have different compositions.

9. The substrate processing method of claim 7 ,
wherein the third film is SiO 2 , SiN, SiC, SiON, or SiOCH 3 .

10. The substrate processing method of claim 7 ,
wherein the second film is SiN, and the third film is SiO 2 .

11. The substrate processing method of claim 2 ,
wherein a halogen of the halogen-containing gas includes one or more of fluorine, chlorine, bromine, and iodine.

12. The substrate processing method of claim 11 ,
wherein the halogen-containing gas does not include carbon.

13. The substrate processing method of claim 11 ,
wherein the halogen-containing gas includes one or more of NF 3 , SF 6 , Cl 2 , HCl, BCl 3 , HBr, Br 2 and HI.

14. The substrate processing method of claim 2 ,
wherein the silicon-containing gas includes one or more of SiCl 4 , SiF 4 , SiH 4 and SiH 2 Cl 2 .

15. The substrate processing method of claim 2 ,
wherein the mixed gas further includes a dilution gas, and
a flow rate of the dilution gas is equal to or larger than 70% of a total flow rate of the mixed gas.

16. The substrate processing method of claim 15 ,
wherein the dilution gas is a rare gas.

17. The substrate processing method of claim 16 ,
wherein the mixed gas is composed of NF 3 or SF 6 ; SiCl 4 or SiF 4 ; and Ar only.

18. The substrate processing method of claim 2 ,
wherein in the etching of the first film, a RF bias power is not applied.

Assignees

• Tokyo Electron Ltd

Inventors

• Inoue Masaki
• Thomas Cedric

Classifications

• H10P72/0421

  for drying etching · CPC title

• H10P50/242 Primary

  of Group IV materials · CPC title

• H10P76/4085

  characterised by the processes involved to create the masks · CPC title

• H01J37/3244 Primary

  Gas supply means · CPC title

• H01J2237/334

  Etching · CPC title