Manufacturing method of semiconductor devices
A semiconductor device manufacturing method includes: depositing a first insulating film and a second insulating film on a substrate sequentially and forming a pattern on the second insulating film; forming a silicon film on the pattern; forming a sidewall made of the silicon film by processing the silicon film until a part of the second insulating film is exposed by use of etch-back; removing the second insulating film; and performing dry etching by use of a fluorocarbon-based gas, to process the first insulating film by using the sidewall as a mask. The processing of the first insulating film includes applying on the substrate a self-bias voltage Vdc that satisfies a relational expression of Vdc<46x−890, where a film thickness of the silicon film that constitutes the sidewall is x nm (19.5≦x≦22.1).
1. A semiconductor device manufacturing method comprising:
depositing a first insulating film and a second insulating film above a substrate sequentially and forming a pattern on the second insulating film;
forming a silicon film on the pattern;
forming a sidewall made of the silicon film by processing the silicon film until a part of the second insulating film is exposed by use of etch-back;
removing the second insulating film; and
performing dry etching by use of a fluorocarbon-based gas, to process the first insulating film by using the sidewall as a mask,
wherein processing of the first insulating film comprises applying on the substrate a self-bias voltage Vdc that satisfies a relational expression of Vdc<46x−890, where a film thickness of the silicon film that constitutes the sidewall is x nm (19.5≦x≦22.1).
2. The method of claim 1 ,
wherein the processing of the first insulating film is performed by using a dry etching apparatus capable of supplying a plurality of high-frequency powers to an electrode on a side of the substrate, and by setting the lower-frequency power of the plurality of high-frequency powers to 0 W during the dry etching.
3. The method of claim 1 ,
wherein the silicon film is amorphous.
4. The method of claim 1 ,
wherein the silicon film is formed at 600° C. or less.
5. The method of claim 4 ,
wherein the processing of the first insulating film comprises forming by the dry etching a trench in which an interconnection line is to be embedded, in the first insulating film.
6. The method of claim 1 ,
wherein the processing of the first insulating film comprises performing the dry etching by using a mixture gas containing octafluoro-cyclobutane (C 4 F 8 ), carbon monoxide (CO) and argon (Ar).
7. The method of claim 1 ,
wherein a combination of the first and second insulating films is a combination of a silicon oxide film and a silicon nitride film.
8. The method of claim 1 ,
wherein a combination of the first and second insulating films is a combination of a silicon oxide film and a film containing carbon as its main component.
9. The method of claim 1 ,
wherein a combination of the first and second insulating films is a combination of a silicon nitride film and a silicon oxide film.
10. The method of claim 1 ,
wherein a combination of the first and second insulating films is a combination of a silicon nitride film and a film containing carbon as its main component.
11. A semiconductor device manufacturing method comprising:
depositing a first insulating film and a second insulating film above a substrate sequentially and forming a pattern on the second insulating film;
forming a silicon film on the pattern;
forming a sidewall made of the silicon film by processing the silicon film until a part of the second insulating film is exposed by use of etch-back;
removing the second insulating film; and
performing dry etching by use of a fluorocarbon-based gas, to process the first insulating film by using the sidewall as a mask,
wherein processing of the first insulating film is carried out by using a semiconductor manufacturing apparatus comprising a reaction chamber, a substrate mounting table, a first power supply capable of supplying the substrate mounting table with a power having a first frequency, a second power supply capable of supplying the substrate mounting table with a power having a second frequency higher than the first frequency, and a blocking capacitor interposed between the substrate mounting table and the first and second power supplies, and by supplying the substrate mounting table with the power from the second power supply in a condition where supply of the power from the first power supply is halted.
12. The method of claim 11 ,
wherein the silicon film is amorphous.
13. The method of claim 11 ,
wherein the silicon film is formed at 600° C. or less.
14. The method of claim 13 ,
wherein the processing of the first insulating film comprises forming by the dry etching a trench in which an interconnection line is to be embedded, in the first insulating film.
15. The method of claim 14 , wherein the silicon film that constitutes the sidewall has a film thickness of 30 nm or less.
16. The method of claim 11 ,
wherein the processing of the first insulating film comprises performing the dry etching by using a mixture gas containing octafluoro-cyclobutane (C 4 F 8 ), carbon monoxide (CO) and argon (Ar).
17. The method of claim 11 ,
wherein a combination of the first and second insulating films is a combination of a silicon oxide film and a silicon nitride film.
18. The method of claim 11 ,
wherein a combination of the first and second insulating films is a combination of a silicon oxide film and a film containing carbon as its main component.
19. The method of claim 11 ,
wherein a combination of the first and second insulating films is a combination of a silicon nitride film and a silicon oxide film.
20. The method of claim 11 ,
wherein a combination of the first and second insulating films is a combination of a silicon nitride film and a film containing carbon as its main component.