SYSTEM FOR MEASURING POLARIMETRIC SPECTRUM AND OTHER PROPERTIES OF A SAMPLE

摘要

A polarized sample beam (12) of broadband radiation is focused onto the surface of a sample (3) and the radiation modified by the sample is collected by means of a mirror system (16) in different planes of incidence. The sample beam focused to the sample has a multitude of polarization states. The modified radiation is analyzed with respect to a polarization plane to provide a polarimetric spectrum. Preferably the polarization of the sample beam is altered only by the focusing and the sample, and the analyzing is done with respect to a fixed polarization plane. In the preferred embodiment, the focusing of the sample beam and the collection of the modified radiation are repeated employing two different apertures (30) to detect the presence or absence of a birefringence axis in the sample. In another preferred embodiment, the above-described technique may be combined with ellipsometry for determining the thickness and refractive indices of thin films.