Claims
- 1. A method of cleaning an area of a metal conductor exposed in at least one opening in a low-κ dielectric on a semiconductor workpiece, comprising the steps of:
providing a semiconductor workpiece that includes a dielectric having at least one opening exposing an area of a metal conductor, wherein the dielectric has a dielectric constant less than or equal to 3.0; and exposing the workpiece to an atmosphere produced by plasma decomposition of a gas mixture, wherein the gas mixture includes helium and at least one hydrogen-containing gas species.
- 2. A method of cleaning an area of a metal conductor exposed in at least one opening in a carbon-containing dielectric on a semiconductor workpiece, comprising the steps of:
providing a semiconductor workpiece that includes a carbon-containing dielectric overlying a metal conductor, wherein the dielectric includes at least one opening exposing an area of the metal conductor; and exposing the workpiece to an atmosphere produced by plasma decomposition of a gas mixture, wherein the gas mixture includes helium and at least one hydrogen-containing gas species.
- 3. A method according to claim 2, wherein the dielectric has a dielectric constant less than 3.8.
- 4. A method according to claim 2, wherein the dielectric has a dielectric constant less than or equal to 3.0.
- 5. A method according to claim 2, wherein the dielectric is an oxide of silicon having a chemical structure that incorporates carbon.
- 6. A method according to claim 2, wherein the dielectric contains at least five percent carbon by weight.
- 7. A method according to claim 2, further comprising the step of:
subsequent to the exposing step, annealing the workpiece at a temperature and for a duration sufficient to reduce the dielectric constant of the dielectric relative to the value of said dielectric constant after the providing step and prior to the annealing step.
- 8. A method according to claim 2, further comprising the step of:
subsequent to the exposing step, annealing the workpiece at a temperature of at least 300° C.
- 9. A method according to claim 2, wherein the providing step is performed for a time long enough to remove substantially all native oxide from said exposed area of the metal conductor.
- 10. A method according to claim 2, wherein the gas mixture has an atomic molar concentration of hydrogen no greater than twenty percent.
- 11. A method according to claim 2, wherein the gas mixture has a atomic molar concentration of hydrogen no greater than ten percent.
- 12. A method according to claim 2, wherein the hydrogen-containing species is H2 gas.
- 13. A method according to claim 12, wherein the gas mixture has a molecular molar concentration of H2 gas no greater than ten percent.
- 14. A method according to claim 12, wherein the gas mixture has a molecular molar concentration of H2 gas no greater than five percent.
- 15. A method according to claim 2, wherein the gas mixture does not include argon.
- 16. A method according to claim 2, wherein the gas mixture does not include BCl3, argon, or any compound of any element having an atomic mass greater than the atomic mass of argon.
- 17. A method according to claim 2, wherein the metal conductor is copper.
- 18. A method of repairing damage to a carbon-containing dielectric on a semiconductor workpiece caused by a plasma process for stripping resist from a surface of the dielectric, comprising the steps of:
providing a semiconductor workpiece that includes a carbon-containing dielectric and an organic resist material overlying portions of the dielectric; removing the resist material by exposing the workpiece to a first atmosphere produced by plasma decomposition of at least one gas, wherein the at least one gas includes oxygen; and subsequently exposing the workpiece to a second atmosphere produced by plasma decomposition of a gas mixture, wherein the gas mixture includes helium and at least one hydrogen-containing gas species.
- 19. A method according to claim 18, wherein:
the workpiece further comprises a metal conductor underlying the dielectric; the dielectric includes at least one opening exposing an area of the metal conductor; and the step of exposing the workpiece to the second atmosphere is performed for a time long enough to remove substantially all native oxide from the exposed area of the metal conductor.
- 20. A method according to claim 18, wherein the dielectric has a dielectric constant less than 3.8.
- 21. A method according to claim 18, wherein the dielectric is an oxide of silicon having a chemical structure that incorporates carbon.
- 22. A method according to claim 18, wherein the dielectric contains at least five percent carbon by weight.
- 23. A method of cleaning an exposed surface of a metal conductor on a semiconductor workpiece, comprising the steps of:
positioning within a vacuum chamber a semiconductor workpiece that includes a metal conductor having an exposed surface; and while the workpiece is within the vacuum chamber, providing within the vacuum chamber an atmosphere produced by plasma decomposition of a gas mixture, wherein the gas mixture includes helium and at least one hydrogen-containing gas species.
- 24. A method according to claim 23, wherein the gas mixture has an atomic molar concentration of hydrogen no greater than twenty percent.
- 25. A method according to claim 23, wherein the gas mixture has a atomic molar concentration of hydrogen no greater than ten percent.
- 26. A method according to claim 23, wherein the hydrogen-containing species is H2 gas.
- 27. A method according to claim 26, wherein the gas mixture has a molecular molar concentration of H2 gas no greater than ten percent.
- 28. A method according to claim 26, wherein the gas mixture has a molecular molar concentration of H2 gas no greater than five percent.
- 29. A method according to claim 23, wherein the gas mixture does not include argon.
- 30. A method according to claim 23, wherein the gas mixture does not include BCl3, argon, or any compound of any element having an atomic mass greater than the atomic mass of argon.
- 31. A method according to claim 23, wherein the providing step further comprises the steps of:
supplying the gas mixture into the vacuum chamber; and inductively coupling RF power to the gas mixture within the vacuum chamber so as to form a plasma.
- 32. A method according to claim 23, wherein the providing step further comprises the steps of:
supplying the gas mixture to a remote plasma chamber; coupling electromagnetic power to the gas mixture to form a plasma that includes reactive species produced by plasma decomposition of the gas mixture; and supplying said reactive species from the remote plasma chamber to the vacuum chamber.
- 33. A method according to claim 23, wherein the providing step is performed for a time long enough to remove substantially all native oxide from said exposed surface.
- 34. A method of cleaning an area of a metal conductor exposed in at least one opening in a dielectric on a semiconductor workpiece, comprising the steps of:
providing a semiconductor workpiece that includes a dielectric having at least one opening exposing an area of a metal conductor; exposing the workpiece to an atmosphere produced by plasma decomposition of a gas mixture, wherein the gas mixture includes helium and at least one hydrogen-containing gas species; and subsequent to the exposing step, annealing the workpiece at a temperature and for a duration sufficient to reduce the dielectric constant of the dielectric relative to the value of said dielectric constant after the providing step and prior to the annealing step.
- 35. A method according to claim 34, wherein said temperature is at least 300° C.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application is a divisional of Ser. No. 09/388,991 filed 9/2/99, now U.S. Pat. No. 6,346,489.
Divisions (1)
|
Number |
Date |
Country |
Parent |
09388991 |
Sep 1999 |
US |
Child |
10075510 |
Feb 2002 |
US |