Optical characteristic and material layer thickness determination method

摘要

The method involves irradiating polarized light on a sample to be examined, and measuring the polarization difference in the light reflected from the sample. A multifrequency calibration measurement is performed before the actual measurement on the sample, whereby the frequency dependency of the attenuation constant and the phase shift are determined and evaluated. After the calibration, the frequency of a rotating optical component is measured for each rotation and the measured intensity of the reflected ray of light is subsequently corrected through modulation with the rotation frequency of the optical component.