Patent ID: 6882421

Claim:
A system for evaluating the nitrogen content in a thin film dielectric layer formed on a sample, comprising: a source of quasi-monochromatic light for generating a first probe beam of a known wavelength, the first probe beam directed to reflect off the surface of the sample at a non-normal angle of incidence; a first detector system for monitoring a change in polarization state of the first probe beam induced by the interaction with the sample and generating first output signals in response thereto; a source of polychromatic light for generating a second probe beam directed to reflect off the surface of the sample; a second detector system for monitoring the second probe beam after reflection from the sample and determining one of a magnitude and a change in polarization state thereof at a plurality of wavelengths and generating a plurality of second output signals corresponding thereto; and a processor for receiving the first and second output signals and evaluating the nitrogen content of the thin film dielectric layer based on a combination of the first and second output signals.