Claims
- 1. A method of forming a polycrystalline cobaltdisilicide (CoSi2) on a silicon substrate, comprising the steps of:
depositing a first layer comprising cobalt on at least a part of said substrate, said part comprising at least a first and a second part; depositing a metal getter layer on said first layer; thereafter heating said silicon substrate in a first heating step, said first heating step being performed at a first temperature being such that a silicidecobalt is formed on said first part; treating said substrate with at least one chemical solution to remove unwanted matter from said substrate; and thereafter heating said substrate in a second heating step to thereby form said polycrystalline cobaltdisilicide layer on said first part of said substrate.
- 2. The method as recited in claim 1, wherein said silicidecobalt is cobaltsilicide (CoSi).
- 3. The method as recited in claim 1, wherein during the chemical solution treatment, a passivation layer is grown on top of the silicidecobalt being formed on said first part of said substrate.
- 4. The method as recited in claim 3, wherein said passivation layer is a thin layer.
- 5. The method as recited in claim 4, wherein said passivation layer is having a thickness of about 5 nm.
- 6. The method as recited in claim 1, wherein said getter layer consists essentially of a refractory metal.
- 7. The method as recited in claim 6, wherein said refractory metal is titanium.
- 8. The method as recited in claim 1, wherein said chemical solution comprises NH4OH.
- 9. The method as recited in claim 1, wherein said chemical solution comprises H2SO4.
- 10. The method as recited in claim 1, wherein said first layer has a thickness in the range of 5-50 nm, and said titanium layer has a thickness in the range of 1-50 nm.
- 11. The method as recited in claim 1, wherein said first layer has a thickness of 15 nm, and said titanium layer has a thickness of 8 nm.
- 12. The method as recited in claim 1, wherein said second heating step is being performed at a higher temperature than said first temperature.
- 13. The method as recited in claim 1, wherein said first heating step is performed in the range of 400-700° C. for a period of time comprised between 10-100 seconds and said second heating step is performed in the range of 600-1000° C. for a period of time between 10-100 seconds.
- 14. The method as recited in claim 1, wherein said first heating step is performed at 550° C. for a period of time of 60 seconds and said second heating step is performed at 700° C. for a period of time of 30 seconds.
- 15. The method as recited in claim 1, wherein said deposition steps are performed by sputter deposition in a vacuum system without breaking the vacuum conditions inbetween subsequent deposition steps.
- 16. The method as recited in claim 1, wherein said polycrystalline cobaltdisilicide is a self-aligned cobaltdisilicide on a metal oxide semiconductor transistor in a silicon substrate, said transistor having an actual gate length of about 0.25 μm or smaller and having a source region, a drain region, and a gate region.
- 17. The method as recited in claim 16, further comprising the steps of:
defining an active area within said silicon substrate; growing an oxide on at least within part of said active area of said substrate; depositing a polysilicon layer on said oxide; and defining said gate region, said source region, and said drain region of said transistor within said active area, said gate region, said source region and said drain region forming said first part.
- 18. The method as recited in claim 1, wherein said polycrystalline cobaltdisilicide is a self-aligned cobaltdisilicide on a metal oxide semiconductor transistor in a silicon substrate, said transistor having an actual gate length of about 0.18 μm or smaller and having a source region, a drain region, and a gate region.
- 19. A method as recited in claim 18, further comprising the steps of:
defining an active area within said silicon substrate; growing an oxide on at least within part of said active area of said substrate; depositing a polysilicon layer on said oxide; and defining said gate region, said source region, and said drain region of said transistor within said active area, said gate region, said source region and said drain region forming said first part.
- 20. A method of forming a polycrystalline cobaltdisilicide on a silicon substrate, comprising the steps of:
depositing a layer structure on at least a part of said substrate, said layer structure comprising cobalt and a refractory metal, said substrate comprising at least a first and a second part; thereafter heating said silicon substrate in a first heating step, said first heating step being performed at a first temperature being such that said first heating step forms a silicidecobalt on said first part; treating said substrate with at least one chemical solution, said chemical solution selectively removing the remaining non-silicidecobalt and said refractory metal and cobalt refractory metal alloys from said substrate; and thereafter heating said substrate in a second heating step to thereby form said polycrystalline cobaltdisilicide layer on said first part of said substrate.
- 21. The method as recited in claim 20, wherein said deposition step is executed by sputter deposition in a vacuum system using a sputter target comprising a mixture of cobalt and said refractory metal.
- 22. The method as recited in claim 20, wherein said second heating step is being performed at a higher temperature than said first temperature.
- 23. A method of forming a polycrystalline nickelsilicide (NiSi) on a silicon substrate, comprising the steps of:
depositing a first layer comprising nickel on at least a part of said substrate, said part comprising at least a first and a second part; depositing a metal getter layer on said first layer; thereafter heating said silicon substrate in a first heating step, said first heating step being performed at a first temperature being such that a silicidenickel is formed on said first part; treating said substrate with at least one chemical solution, said chemical solution selectively removing the remaining non-silicidenickel and/or said getter metal and/or nickel and/or nickel-getter-metal alloys from said substrate; and thereafter heating said substrate in a second heating step to thereby form said polycrystalline nickelsilicide layer on said first part of said substrate.
- 24. A method of forming a polycrystalline palladiumsilicide (Pd2Si) on a silicon substrate, comprising the steps of:
depositing a first layer comprising palladium on at least a part of said substrate, said part comprising at least a first and a second part; depositing a metal getter layer on said first layer; thereafter heating said silicon substrate in a first heating step, said first heating step being performed at a first temperature being such that a silicidepalladium is formed on said first part; treating said substrate with at least one chemical solution, said chemical solution selectively removing the remaining non-silicidepalladium and/or said getter metal and/or palladium and/or palladium-getter-metal alloys from said substrate; and thereafter heating said substrate in a second heating step to thereby form said polycrystalline palladiumsilicide layer on said first part of said substrate.
- 25. A method of forming a polycrystalline platinumsilicide (PtSi) on a silicon substrate, comprising the steps of:
depositing a first layer comprising platinum on at least a part of said substrate, said part comprising at least a first and a second part; depositing a metal getter layer on said first layer; thereafter heating said silicon substrate in a first heating step, said first heating step being performed at a first temperature being such that a silicideplatinum is formed on said first part; treating said substrate with at least one chemical solution, said chemical solution selectively removing the remaining non-silicideplatinum and/or said getter metal and/or platinum and/or platinum-getter-metal alloys from said substrate; and thereafter heating said substrate in a second heating step to thereby form said polycrystalline platinumsilicide layer on said first part of said substrate.
- 26. The method as recited in claim 1, wherein said chemical solution can selectively remove remaining non-silicidecobalt, said getter metal, cobalt, cobalt-getter-metal alloys from said substrate.
Parent Case Info
[0001] RELATED APPLICATIONS
[0002] The present Patent Application is a continuation in part of U.S. patent application Ser. No. 09/055645, which is a continuation in part of U.S. patent application Ser. No. 08/658,182, and claims the benefit of the corresponding priorities.
Continuations (1)
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Number |
Date |
Country |
Parent |
09055645 |
Apr 1998 |
US |
Child |
09309455 |
Jun 1998 |
US |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
08658182 |
Jun 1996 |
US |
Child |
09055645 |
Apr 1998 |
US |