Nova Ltd.
METHOD AND SYSTEM FOR OPTICAL METROLOGY IN PATTERNED STRUCTURES

Abstract:

Determining parameters of a patterned structure located on top of an underneath layered structure, where input data is provided which includes first measured data PMD being a function f of spectral intensity I.sub..lamda. and phase .PHI., PMD=f(I.sub..lamda.; .PHI.), corresponding to a complex spectral response of the underneath layered structure, and second measured data S.sub.meas indicative of specular reflection spectral response of a sample formed by the patterned structure and the underneath layered structure, and where a general function F is also provided describing a relation between a theoretical optical response S.sub.theor of the sample and a modeled optical response S.sub.model of the patterned structure and the complex spectral response PMD of the underneath layered structure, such that S.sub.theor=F(S.sub.model; PMD), where the general function is then utilized for comparing the second measured data S.sub.meas and the theoretical optical response S.sub.theor, and determining parameter(s) of interest of the top structure.