APPARATUS FOR DETECTING HAZES OF PHOTOMASK SURFACE USING REAL-TIME BACKGROUND-FREE DETECTION OF NANOSCALE PARTICLES AND METHOD FOR DETECTING THEREOF

摘要

An apparatus for detecting haze on the surface of a photomask by a nanoscale detection method is provided to quantitatively analyze the cause of formation of haze, by controlling the environment in a chamber, by measuring exposure energy and by enabling a real-time detection of generated haze. Laser(10) causes formation of haze. A system controls a variation of a laser beam and a photomask surface and a haze generation position so as to measure the energy intensity of a beam reaching a photomask(19) in real time. In real time, a haze detection unit(30) detects in real time whether haze is generated. Measurement light separated from monochromatic light is irradiated and scattered while modifying he coordinates of the photomask surface. The scattered light is recombined with reference light separated from the monochromatic light to generate interference pattern light. The haze detection init receives the interference pattern light by using a separated optical detection unit to detect in real time whether haze is generated.