<title>Soft-defect inspection equipment based on DIC technique</title>

Abstract

We have recently presented an operational principle based on the differential interference contrast (DIC) technique that we call `A-DIC method.' This method can suppress the circuit pattern images, and enhance the contrast between the images of the contamination and the defect-less circuit patterns. It uses both the transmission and reflection images. In this paper, we describe the other simpler method that we call `B- DIC' method.' This method requires only the reflection images and can be built in a confocal scanning microscope.