Spectral linewidth adjusting method and electronic device manufacturing method

An electronic device manufacturing method comprising:

• generating a fourth pulse laser beam by a laser apparatus, the laser apparatus including
• a first semiconductor laser configured to output first continuous light,
• a first amplifier configured to amplify a portion of the first continuous light in synchronization with a light emission trigger signal received from an external device and to convert the portion of the first continuous light to a first pulse laser beam,
• a second amplifier configured to amplify a portion of the first pulse laser beam using a first trigger signal generated in synchronization with the light emission trigger signal and to convert the portion of the first pulse laser beam to a second pulse laser beam,
• a second semiconductor laser configured to output second continuous light,
• a third amplifier configured to amplify a portion of the second continuous light using a second trigger signal generated in synchronization with the light emission trigger signal and to convert the portion of the second continuous light to a third pulse laser beam,
• an optical phase modulator disposed in an optical path of the second continuous light between the second semiconductor laser and the third amplifier,
• a modulation signal generator configured to output a modulation signal to be supplied to the optical phase modulator, and
• a wavelength conversion system configured to perform sum-frequency mixing of the second pulse laser beam and the third pulse laser beam for wavelength conversion and to output the fourth pulse laser beam,
• the laser apparatus adjusting at least one of a timing of the first trigger signal and a timing of the second trigger signal and adjusting a spectrum of the fourth pulse laser beam to a first spectrum in a non-Gaussian shape, and
• the laser apparatus modulating a wavelength of the second continuous light within time corresponding to one pulse of the third pulse laser beam and adjusting the spectrum of the fourth pulse laser beam to a second spectrum having a spectral linewidth wider than the first spectrum by causing the modulation signal generator to generate the modulation signal of a same pattern synchronized with the light emission trigger signal and supplying the modulation signal of the same pattern to the optical phase modulator;
• outputting the fourth pulse laser beam to an exposure apparatus;
• and
• exposing a photosensitive substrate to the fourth pulse laser beam within the exposure apparatus to manufacture an electronic device.