Claims
- 1. A tunable laser system, comprising:
a gain medium and an optical resonator for generating a laser beam a spectral narrowing and tuning unit within the resonator; a detection and control unit for relative wavelength detection and control; and a wavelength calibration module for calibrating the detection and control unit, said module containing a plurality of species each having an optical transition line within the tuning range of said laser,
wherein a beam portion of the narrowed emission from said laser is directed through the wavelength calibration module and a beam portion is directed through the detection and control unit when the laser beam is scanned through said optical transition line of each of said plurality of species and said detection and control unit is monitored for calibrating said detection and control unit.
- 2. The laser system of claim 1, wherein the detection and control unit includes a monitor etalon and an array detector.
- 3. The laser system of claim 2, wherein a free spectral range of the monitor etalon is determined by counting a number a interference fringes between the plurality of optical transition lines.
- 4. The laser system of claim 1, wherein the spectral narrowing and tuning unit is also calibrated when the laser beam is scanned through said plurality of optical transition lines.
- 5. The laser system of claim 1, wherein the spectral narrowing and tuning unit is further calibrated when the laser beam is scanned and tuning steps of said spectral narrowing and tuning unit are calibrated to the calibrated detection and control unit.
- 6. A tunable laser system, comprising:
a gain medium and an optical resonator for generating a laser beam; a spectral narrowing and tuning unit; and a wavelength calibration module containing a plurality of species each having an optical transition line within the tuning range of said laser,
wherein a beam portion of the narrowed emission from said laser is directed through the wavelength calibration module when the laser beam is scanned through said optical transition line of each of said plurality of species and said spectral narrowing and tuning unit is monitored for calibrating tuning steps of said spectral narrowing and tuning unit.
- 7. The laser system of claim 6, wherein said spectral narrowing and tuning unit includes a rotatable grating for tuning the wavelength of the laser beam and said tuning steps are grating rotation steps.
- 8. The laser system of claim 6, wherein said spectral narrowing and tuning unit includes a rotatable mirror for tuning the wavelength of the laser beam and said tuning steps are mirror rotation steps.
- 9. The laser system of claim 6, wherein said spectral narrowing and tuning unit includes a pressure-adjustable gas-filled enclosure containing an optical element of said resonator for tuning the wavelength of the laser beam and said tuning steps are amounts of pressure.
- 10. The tunable laser of any of claims 1 or 6, wherein said laser system is an ArF laser system emitting around 1 93 nm and said plurality of species are selected from the group consisting of arsenic, carbon, germanium, cobalt, iron, hydrocarbons, halogenized hydrocarbons, carbon-contaminated inert gases, oxygen and platinum vapor.
- 11. The laser system of claim 10, wherein said plurality of species include iron and germanium.
- 12. The laser system of claim 10, wherein said plurality of species include iron and platinum.
- 13. The laser system of claim 10, wherein said plurality of species include germanium and platinum.
- 14. The laser system of claim 10, wherein said wavelength calibration module further contains a buffer gas.
- 15. The laser system of claim 14, wherein said buffer gas contained within said wavelength calibration module includes krypton.
- 16. The laser system of any of claims 1 or 6, wherein said wavelength calibration module includes a first cathode made of a first material of said plurality of species and a second cathode made of a second material of said at plurality of species different than said first material.
- 17. The laser system of claim 16, wherein said wavelength calibration module includes a single lamp module, wherein said first and second cathodes are disposed within separated first and second chambers of said single lamp module.
- 18. The laser system of claim 16, wherein said wavelength calibration module includes two lamp modules, wherein said first cathode is disposed within said first lamp module and said second cathode is disposed within said second lamp module.
- 19. The laser system of claim 16, wherein said wavelength calibration module further contains a buffer gas.
- 20. The laser system of claim 19, wherein said buffer gas contained within said wavelength calibration module includes krypton.
- 21. The laser system of any of claims 1 or 6, wherein said wavelength calibration module includes a cathode made of a first material of said plurality of species and a gaseous species of said plurality of species different from the species of said first material.
- 22. The laser system of claim 21, wherein said wavelength calibration module further contains a buffer gas including krypton.
- 23. The laser system of any of claims 1 or 6, wherein said wavelength calibration module includes a first gaseous species of said plurality of species and a second gaseous species of said plurality of species different from the first gaseous species.
- 24. The laser system of claim 23, wherein said wavelength calibration module further contains a buffer gas including krypton.
- 25. The tunable laser of any of claims 1 or 6, wherein said laser system is a F2 laser system emitting around 157 nm and said at least two species are selected from the group consisting of bromine, silicon and selenium.
- 26. The laser system of claim 25, wherein said at least two species include bromine and silicon.
- 27. The laser system of claim 25, wherein said at least two species include bromine and selenium.
- 28. The laser system of claim 25, wherein said at least two species include selenium and silicon.
- 29. A tunable laser system, comprising:
a gain medium and an optical resonator for generating a laser beam a spectral narrowing and tuning unit within the resonator; a detection and control unit for relative wavelength detection and control; and a wavelength calibration module for calibrating the detection and control unit, said module containing at least one species having an optical transition line within the tuning range of said laser and a buffer gas,
wherein a beam portion of the narrowed emission from said laser is directed through the wavelength calibration module and a beam portion is directed through the detection and control unit when the laser beam is scanned through said optical transition line of the at least one species and said detection and control unit is monitored for calibrating said detection and control unit.
- 30. The laser system of claim 29, wherein said buffer gas includes krypton.
- 31. The laser system of claim 29, wherein said buffer gas includes neon.
- 32. The laser system of claim 29, wherein said buffer gas includes helium.
- 33. The laser system of claim 29, wherein said buffer gas includes xenon.
- 34. The laser system of claim 29, wherein the detection and control unit includes a monitor etalon and an array detector.
- 35. The laser system of claim 34, wherein a free spectral range of the monitor etalon is determined by counting a number a interference fringes between the plurality of optical transition lines.
- 36. The laser system of claim 29, wherein the spectral narrowing and tuning unit is also calibrated when the laser beam is scanned through said plurality of optical transition lines.
- 37. The laser system of claim 29, wherein the spectral narrowing and tuning unit is further calibrated when the laser beam is scanned and tuning steps of said spectral narrowing and tuning unit are calibrated to the calibrated detection and control unit.
- 38. A method for calibrating a wavelength detection and control unit of a tunable laser system having a wavelength calibration module containing a plurality of species each having an optical transition line within the tuning range of said laser, comprising the steps of:
generating a line-narrowed laser beam; directing a narrowed beam portion through the wavelength calibration module; directing a narrowed beam portion through the detection and control unit; scanning the laser beam through said optical transition line of each of said plurality of species; and monitoring the detection and control unit during said scanning for calibrating said detection and control unit.
- 39. The method of claim 38, wherein the detection and control unit includes a monitor etalon and an array detector, and wherein a free spectral range of the monitor etalon is determined by counting a number of interference fringes between the plurality of optical transition lines.
- 40. The method of claim 38, further comprising the step of calibrating the spectral narrowing and tuning unit when the laser beam is scanned through said plurality of optical transition lines.
- 41. The method of claim 38, further comprising the step of calibrating the spectral narrowing and tuning unit when the laser beam is scanned and tuning steps of said spectral narrowing and tuning unit are calibrated to the calibrated detection and control unit.
- 42. A method for calibrating a wavelength detection and control unit of a tunable laser system having a wavelength calibration module containing a plurality of species each having an optical transition line within the tuning range of said laser, comprising the steps of:
generating a line-n arrowed laser beam; directing a narrowed beam portion through the wavelength calibration module; scanning the laser beam through said optical transition line of each of said plurality of species; and monitoring the spectral narrowing and tuning unit for calibrating tuning steps of said spectral narrowing and tuning unit.
- 43. The method of claim 42, wherein said spectral narrowing and tuning unit includes a rotatable grating for tuning the wavelength of the laser beam and said tuning steps are grating rotation steps.
- 44. The method of claim 42, wherein said spectral narrowing and tuning unit includes a rotatable mirror for tuning the wavelength of the laser beam and said tuning steps are mirror rotation steps.
- 45. The method of claim 42, wherein said spectral narrowing and tuning unit includes a pressure-adjustable gas-filled enclosure containing an optical element of said resonator for tuning the wavelength of the laser beam and said tuning steps are amounts of pressure.
- 46. A method for calibrating a wavelength detection and control unit of a tunable laser system having a wavelength calibration module containing at least one species having an optical transition line within the tuning range of said laser, a spectral narrowing and tuning unit, and a wavelength detection and control unit, comprising the steps of:
pressurizing said wavelength calibration module with a buffer gas sufficient to produce marking lines within a tuning spectrum of said laser system; generating a line-narrowed laser beam; directing a narrowed beam portion through the wavelength calibration module; directing a narrowed beam portion through the detection and control unit; scanning the laser beam through said optical transition line of the at least one species; and monitoring the detection and control unit during said scanning for calibrating said detection and control unit.
- 47. The method of claim 46, wherein the detection and control unit includes a monitor etalon and an array detector, and wherein a free spectral range of the monitor etalon is determined by counting a number of interference fringes between the plurality of optical transition lines.
- 48. A method for calibrating a wavelength detection and control unit of a tunable laser system having a wavelength calibration module containing at least one species having an optical transition line within the tuning range of said laser, and a spectral narrowing and tuning unit, comprising the steps of:
pressurizing said wavelength calibration module with a buffer gas sufficient to produce marking lines within a tuning spectrum of said laser system; generating a line-narrowed laser beam; directing a narrowed beam portion through the wavelength calibration module; scanning the laser beam through said optical transition line of the at least one species; and monitoring the spectral narrowing and tuning unit during said scanning for calibrating tuning steps of said spectral narrowing and tuning unit.
- 49. The method of any of claims 46 or 48, wherein said buffer gas includes krypton.
- 50. The method of any of claims 46 or 48, wherein said buffer gas includes neon.
- 51. The method of any of claims 46 or 48, wherein said buffer gas includes helium.
- 52. The method of any of claims 46 or 48, wherein said buffer gas includes xenon.
PRIORITY
[0001] This application claims the benefit of priority to U.S. provisional patent applications No. 60/202,564, filed May 10, 2000, and 60/186,096, filed Mar. 1, 2000.
Provisional Applications (2)
|
Number |
Date |
Country |
|
60202564 |
Jun 2000 |
US |
|
60186096 |
Mar 2000 |
US |