Claims
- 1. A method to etch an electrically conductive film, comprising the steps of:
- forming a metal conductor film comprising a layer consisting essentially of copper upon a substrate; and
- forming a mask pattern, covering a part of said metal conductor film and exposing another part of said metal conductor film upon said metal conductor film; and
- etching said exposed part of said metal conductor film by the use of said mask pattern and a reactive ion-etching (RIE) gas mixture plasma comprising silicon tetra-chloride (SiCl.sub.4) gas, nitrogen (N.sub.2) gas, and a hydrocarbon compound containing gas, whereby said exposed part of said metal conductor film is removed so as to leave a flat etched side of said metal conductor film.
- 2. The method according to claim 1, wherein said copper layer comprises an alloy of silicon in copper.
- 3. The method according to claim 1, wherein said metal conductor film further comprises a diffusion protecting layer comprising a refractory metal.
- 4. The method according to claim 3, wherein said refractory metal is selected from the group consisting of tantalum (Ta), tantalum nitride (TaN), titanium nitride (TiN), titanium tungsten (TiW), tungsten (W), niobium (Nb), chromium (Cr), manganese (Mn), cobalt (Co) and molybdenum (Mo.).
- 5. The method according to claim 1, wherein said mask pattern comprises silicon dioxide (SiO.sub.2).
- 6. The method according to claim 1, wherein said substrate further comprises an insulating layer thereon in contact with said metal conductor film.
- 7. The method according to claim 6, wherein said insulating film comprises silicon dioxide (SiO.sub.2).
- 8. The method according to claim 1, wherein said gas mixture consists essentially of silicon tetra-chloride (SiCl.sub.4) gas, and nitrogen (N.sub.2) gas, and a hydrocarbon compound containing gas.
- 9. The method according to claim 1, wherein said hydrocarbon compound containing gas is at least one member selected from the group consisting of methane (CH.sub.4), ethane (C.sub.2 H.sub.6) and propane (C.sub.3 H.sub.8).
- 10. The method according to claim 9, wherein said hydrocarbon compound containing gas comprises 8 to 18% by volume of said gas mixture plasma.
- 11. The method according to claim 1, wherein said etching is performed at a substrate temperature of higher than 250.degree. C.
- 12. The method according to claim 11, wherein said etching is performed at a substrate temperature of 310.degree. to 330.degree. C.
- 13. The method as claimed in claim 3, wherein said refractory metal is a component of an alloy.
- 14. The method as claimed in claim 3, wherein said diffusion protection layer is disposed between said layer consisting essentially of copper and said substrate.
- 15. The method as claimed in claim 3, wherein said diffusion protection layer is disposed between said layer consisting essentially of copper and said mask.
- 16. The method according to claim 10, wherein said hydrocarbon compound component of said gas is methane.
Priority Claims (1)
Number |
Date |
Country |
Kind |
5-113542 |
May 1993 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 08/187,725 filed Jan. 28, 1994 now abandoned.
US Referenced Citations (7)
Foreign Referenced Citations (2)
Number |
Date |
Country |
433983 |
Jun 1991 |
EPX |
01308028 |
Dec 1989 |
JPX |
Non-Patent Literature Citations (1)
Entry |
Ohno et al., Jap. J. Appl. Phys., vol. 28, No. 6, Jun. 1989, pp. L1070-L1072. |
Continuations (1)
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Number |
Date |
Country |
Parent |
187725 |
Jan 1994 |
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