Laser apparatus and method of manufacturing electronic device

A method of manufacturing an electronic device comprising:

• generating a laser beam with a laser apparatus, the laser apparatus including
• a laser oscillator including an optical resonator and a pair of electrodes that apply a voltage to a laser gas to cause discharge, and configured to output a first pulse laser beam,
• a first optical pulse stretcher disposed in an optical path of the first pulse laser beam, configured to output a second pulse laser beam for which a pulse time width of the first pulse laser beam is extended by transmitting a part of the first pulse laser beam, making the other part circulate once, and outputting first transmitted light and first once-circulating light, and configured such that an optical path of the first transmitted light and an optical path of the first once-circulating light spatially partially overlap with a first shift amount in a first direction, and
• a second optical pulse stretcher disposed in an optical path of the second pulse laser beam, configured to output a third pulse laser beam for which a pulse time width of the second pulse laser beam is extended by transmitting a part of the second pulse laser beam, making the other part circulate once, and outputting second transmitted light and second once-circulating light, and configured such that an optical path of the second transmitted light and an optical path of the second once-circulating light spatially partially overlap with a second shift amount, which is different from the first shift amount, in the first direction;
• outputting the laser beam to an exposure apparatus;
• and
• exposing a photosensitive substrate to the laser beam within the exposure apparatus to manufacture an electronic device.