Patent ID: 6795167
Filing Date: 2004-09-21
Classification: G03F

Abstract:
A projection exposure apparatus, comprising:an illumination optical system for illuminating a pattern of a reticle with laser light from a continuous emission excimer laser; a projection optical system for projecting the illuminated pattern onto a substrate; adjusting means for adjusting an optical characteristic of said projection optical system in accordance with a change in wavelength of the laser; and wavelength stabilizing means for stabilizing the wavelength of the laser light when the adjustment of the optical characteristic of said projection optical system by said adjusting means is insufficient, said wavelength stabilizing means comprising a piezoelectric device, wherein the wavelength of the laser light is adjusted by driving the piezoelectric device, wherein (i) the half bandwidth of a wavelength spectrum of the laser light is not greater than 0.1 pm, (ii) the excimer laser is an ArF excimer laser, and (iii) the projection optical system consists of a refractive lens system constituted essentially by SiO2.