Claims
- 1. A method of forming a metal alloy on a substrate having an upper surface, said method comprising the steps of:
- heating said upper surface of said substrate to a temperature in the range between 300.degree. to 400.degree. C.; and
- flowing a gas containing germanium over said upper surface of said substrate, said upper surface having regions containing exposed aluminum, wherein the germanium in said gas reacts with said aluminum to form an aluminum alloy in-situ.
- 2. A method according to claim 1, wherein said step of flowing a gas includes a gas selected from the group consisting of GeH.sub.4 and Ge.sub.2 H.sub.6.
- 3. A method according to claim 1, further comprising the step of flowing a gas containing W after said step of flowing a gas containing germanium, to thereby form a hard cap layer of W.sub.x Ge.sub.y over said metal alloy for a polishing stop, where the sum of x and y is 1 and both x and y are greater than or equal to 0 and less than or equal to 1.
- 4. A method according to claim 3, further comprising a step of removing said hard cap layer by reactive ion etching.
- 5. A method according to claim 1, wherein said step of flowing a gas containing germanium includes flowing said gas containing germanium at a pressure of 1 mT to 760 Torr.
- 6. A method according to claim 5, wherein said step of flowing a gas containing germanium includes flowing said gas containing germanium at a pressure of 1 Torr.
- 7. A method of filling at least one of vias and lines on a substrate having an upper surface, said method comprising the steps of:
- heating said upper surface of said substrate to a temperature between 300.degree. to 450.degree. C. and at a pressure of less than 1 Torr;
- filling said at least one of vias and lines with a metal selected from the group consisting of Al, Al--Cu, and Cu to thereby fill said at least one of vias and lines; and
- flowing a gas containing germanium over said upper surface, wherein said germanium forms an alloy in-situ with said one Al, Al--Cu, and Cu.
- 8. A method according to claim 7, wherein said step of heating includes heating said substrate at a temperature between 350.degree. and 400.degree. C.
- 9. A method according to claim 8, further comprising the step of flowing a gas containing tungsten over said upper surface of said substrate, to thereby produce a hard cap of W.sub.x Ge.sub.y, where the sum of x and y is 1 and both x and y are greater than or equal to 0 and less than or equal to 1.
- 10. A method according to claim 7, wherein said step of heating including heating said upper surface at a temperature between 350.degree. and 400.degree. C. and at pressures of between 0.2 mT to 0.8 mT.
- 11. A method according to claim 7, wherein said at least one of vias and lines comprise a high aspect ratio greater than 3.
- 12. A method according to claim 7, wherein said at least one of vias and lines comprise a high aspect ratio greater than 4.
RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 08/479,406, filed on Jun. 7, 1995, now abandoned, which is a divisional of U.S. patent application Ser. No. 08/286,605, filed Aug. 5, 1994, now abandoned.
US Referenced Citations (11)
Foreign Referenced Citations (1)
Number |
Date |
Country |
499050A1 |
Aug 1992 |
EPX |
Non-Patent Literature Citations (2)
Entry |
K. Kikuta et al.; "Al-Ge Reflow Sputtering for Submicron-Contact-Hole Filling"; VMIC Conference, Jun. 11-12, 1991, pp. 163-169. |
K. Kikuta et al.; "0.25 .mu.m Contact Hole Filling by Al-Ge Reflow Sputtering"; 1991 Symposium on VLSI Technology, Digest of Technical Papers, May 28-30, 1991 pp. 35-36. |
Divisions (1)
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Number |
Date |
Country |
Parent |
286605 |
Aug 1994 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
479406 |
Jun 1995 |
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