SPECTROSCOPIC ELLIPSOMETER USING ACOUSTIC-OPTIC TUNABLE FILTER AND ELLIPSOMETRY USING THEREOF

摘要

A spectroscopic ellipsometer using an acoustic-optic tunable filter and an ellipsometric method using the same are provided to implement a spectroscopic ellipsometer including a spectral imaging ellipsometer more conveniently by using an acoustic-optic tunable filter(40) as both spectral and polarization devices. A spectroscopic ellipsometer includes a light source(2) emitting homogeneous light; a specimen part(3) in which the homogeneous light emitted from the light source is reflected; a polarization and modulation part(4) which includes an acoustic-optic tunable filter(40) having a wavelength bandwidth determined according to the homogeneous light reflected from the specimen part and an RF signal(63) from an acoustic-optic tunable filter driver(61), and generates two diffracted lights whose wave fronts are perpendicular to each other; a detection unit(5) measuring the two diffracted lights from the acoustic-optic tunable filter(40) to a two-dimensional imaging device at the same time and compensating for the polarized light confusion error generated in the acoustic-optic tunable filter; and a signal processing control part(6) synchronizing and controlling the two-dimensional imaging device to compensate for the polarized light confusion error and calculating the refractive index and thickness of specimen.