Patent ID: 7499162
Filing Date: 2009-03-03
Classification: G01N,G02B

Abstract:
1. A method for observing a sample with patterns formed thereon, including the steps for: applying a polarized light to the sample from an optical system set on a first polarizing condition; detecting the light applied to and reflected from the surface of the sample through a phase difference plate and an analyzer, thereby obtaining a first image; displaying the first image on a monitor screen; setting the optical system on a second polarizing condition according to the first image displayed on the monitor screen; applying a polarized light to the sample from the optical system set on the second polarizing condition; and detecting the light applied to and reflected from the surface of the sample through the phase difference plate and the analyzer, to thereby obtain a second image, wherein the phase difference plat is adjusted when the optical system is set in the second polarizing condition, thereby reducing the amplitude of the 0 order diffracted light from a pattern formed on the surface of the sample more than the amplitude of the higher-order diffracted light, both of the 0 order and higher-order diffracted light being included in the light reflected from the surface of the sample.