| 摘要 |
<p>A projection exposure system is disclosed, which includes: a laser; a mask stage for supporting a photomask; a wafer stage for supporting a wafer; an illumination optical system effective to illuminate the photomask by use of a light from the laser; a projection optical system for projecting, upon the wafer, a circuit pattern formed on the photomask; an adjusting device for adjusting the wavelength to be emitted from the laser; a discharge tube disposed on a path for at least a portion of the light from the laser and being adapted to emit a predetermined line spectrum; a detecting device for detecting a change in a discharged electric current from the discharge tube; and a control device for controlling the adjusting device on the basis of an output signal from the detecting device.</p> |
