METHOD AND SYSTEM FOR OPTICAL METROLOGY IN PATTERNED STRUCTURES

摘要

A data analysis method and system are presented for use in determining one or more parameters of a patterned structure located on top of an underneath layered structure. According to this technique, input data is provided which includes first measured data PMD being a function f of spectral intensity Iλ and phase φ, PMD=f(I λ ;φ), corresponding to a complex spectral response of the underneath layered structure, and second measured data S meas indicative of specular reflection spectral response of a sample formed by the patterned structure and the underneath layered structure. Also provided is a general function F describing a relation between a theoretical optical response S theor of the sample and a modeled optical response S model of the patterned structure and the complex spectral response PMD of the underneath layered structure, such that S theor =F(S model ; PMD). The general function is then utilized for comparing the second measured data S meas and the theoretical optical response S theor , and determining parameter(s) of interest of the top structure.