| 摘要 |
The present invention aims to provide a polarization modulation imaging ellipsometer capable of measuring ellipsometric parameters of the surface of a sample for each of the measured points with high precision and at high speed. The present invention provides a polarization modulation imaging ellipsometer having a light source unit that emits light whose intensity periodically changes at a predetermined frequency; an incident-light optical unit having a collimator, a polarizer, and a photoelastic phase modulator which modulates light emitted from the light source unit to sinusoidally vary a phase difference between a p polarized light and an s polarized light of the light and applies the light to a measurement plane of the sample; an emitted-light optical unit having an analyzer which analyzes a polarization state of light that has been reflected from or transmitted through the sample and a two-dimensional detector which converts light received from the analyzer to an electrical signal and outputs the electrical signal; and a control/analysis unit which operates the light source unit and the photoelastic phase modulator at the same frequency, wherein the light source unit sequentially produces a measuring beam having a predetermined time lag relative to an operation clock of the photoelastic phase modulator; and the control/analysis unit calculates ellipsometric parameters of each of the measured points using output signals of the two-dimensional detector and calibration values obtained using a standard sample in advance.
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