OPTICAL METHOD AND SYSTEM FOR DEFECTS DETECTION IN THREE-DIMENSIONAL STRUCTURES

摘要

An inspection system and method are presented for inspecting structures having a pattern formed by an array of elongated grooves having high aspect-ratio geometry, such as semiconductor wafers formed with vias. The inspection system comprises an imaging system and a control unit. The imaging system is configured and operable for imaging the structure with a dark-field imaging scheme and generating a dark-field image. The control unit comprises an analyzer module for analyzing pixels brightness in the dark-field image for identifying a defective groove, being a groove characterized by pixels brightness in the dark-field image lower than nominal brightness by a predetermined factor.