Imaging ellipsometry measurement noises associated with non-uniform retardation of the compensator

Owing to high accuracy in the whole measurement range, the compensator-rotating method is a powerful technique for transmission/reflection ellipsometric measurements. The compensator-rotating imaging ellipsometer, which is a system combing the optical microscope and single measurement point ellipsometer, faces non-ideal measurement conditions involving nonuniformity of the retardation across the compensator. In this paper, we study the effect of non-ideal measurement conditions on the measurement noises and introduce the systematic solution.