Patent ID: 7123366
Filing Date: 2006-10-17
Classification: G01B,G01J,H01L

Abstract:
1. A method of optical measurements on a patterned structure having an array of spaced-apart regions of different optical properties and having an uppermost layer of substantially uniform optical properties, the method comprising the steps of: a) providing an optical model, based on features of the structure, defined by a certain process of the structure manufacture, the optical model being configured for determining theoretical data representative of spectral characteristics of light returned from the structure and for calculating a thickness parameter of at least the uppermost layer of the structure; b) applying optical measurements to said structure, by illuminating it with incident radiation of a preset substantially wide wavelength range, detecting light returned from the structure, and obtaining measured data representative of spectral characteristics of the measured returned light within said wavelength range; c) processing and analyzing the measured data using said theoretical data, to determine a thickness of the uppermost layer of the structure under measurements in at least one region of the structure.