Laser oscillating apparatus, exposure apparatus using the same, and device fabrication method

摘要

In a laser oscillating apparatus for exciting a laser gas in a laser tube by introducing an electromagnetic wave from a waveguide (1) into the laser tube (2) through a plurality of slots (10) formed in a waveguide wall, and generating a laser beam by resonating light emitted from the laser gas, the slots (10) are formed in a line such that their longitudinal direction is consistent with the longitudinal direction of the waveguide (1), and a metal wall (12) is so formed as to surround these slots. This metal wall (12) forms a gap as a microwave passage from the slots (10) to a window (15) in the laser tube wall, thereby spacing the laser tube wall apart from the slots (10) by a predetermined distance. <IMAGE>