Patent ID: 6650415
Filing Date: 2003-11-18
Classification: G01J,G01N

Abstract:
A broadband spectroscopic ellipsometer for evaluating a sample comprising:a light generator that generates a beam of polychromatic light having a range of wavelengths and a known polarization; a compensator disposed in the beam path for inducing a phase retardation in the beam and wherein the range of wavelengths of light and the compensator are selected such that an effective phase retardation value is induced covering a range at least from 90 degrees to 180 degrees, said compensator being rotatable about the propagation axis of the beam; an analyzer positioned to interact with the light beam after the light beam interacts with the sample and the compensator; and a detector that measures the intensity of the light beam after the interaction with the analyzer as a function of wavelength and rotational position of the compensator and with the output thereof being used to evaluate the sample.