Laser apparatus, laser apparatus wavelength control method, and electronic device manufacturing method

A laser apparatus wavelength control method comprising:

• outputting a continuously oscillating first seed laser beam having a first wavelength by a first semiconductor laser;
• outputting a continuously oscillating second seed laser beam having a second wavelength different from the first wavelength by a second semiconductor laser;
• outputting selected one of the first seed laser beam and the second seed laser beam as a selected seed laser beam from an optical switch;
• pulsing and amplifying the selected seed laser beam and outputting a first pulse laser beam by a first solid-state amplifier;
• outputting a second pulse laser beam by wavelength conversion using the first pulse laser beam by a wavelength conversion system;
• amplifying the second pulse laser beam and outputting a third pulse laser beam by an excimer amplifier;
• measuring a wavelength of the third pulse laser beam by a beam characteristic measuring instrument;
• and
• selecting one of the first seed laser beam and the second seed laser beam as the selected seed laser beam based on a target wavelength and controlling a wavelength of the first semiconductor laser or the second semiconductor laser that outputs the selected seed laser beam based on the wavelength measured by the beam characteristic measuring instrument such that the wavelength of the third pulse laser beam becomes the target wavelength.

An electronic device manufacturing method comprising:

• generating a laser beam with a laser apparatus, the laser apparatus including
• a first semiconductor laser configured to output a continuously oscillating first seed laser beam having a first wavelength,
• a second semiconductor laser configured to output a continuously oscillating second seed laser beam having a second wavelength different from the first wavelength,
• an optical switch configured to output selected one of the first seed laser beam and the second seed laser beam as a selected seed laser beam,
• a first solid-state amplifier configured to pulse and amplify the selected seed laser beam and to output a first pulse laser beam,
• a wavelength conversion system configured to output a second pulse laser beam by wavelength conversion using the first pulse laser beam,
• an excimer amplifier configured to amplify the second pulse laser beam and to output a third pulse laser beam,
• a beam characteristic measuring instrument configured to measure a wavelength of the third pulse laser beam, and
• a processor configured to select one of the first seed laser beam and the second seed laser beam as the selected seed laser beam based on a target wavelength, and to control a wavelength of the first semiconductor laser or the second semiconductor laser that outputs the selected seed laser beam based on the wavelength measured by the beam characteristic measuring instrument such that the wavelength of the third pulse laser beam becomes the target wavelength;
• outputting the laser beam to an exposure apparatus;
• and
• exposing a photosensitive substrate to the laser beam in the exposure apparatus to manufacture an electronic device.