Metrology method and associated metrology device

Abstract

Disclosed is a method of determining a value for a parameter of interest from a target on a substrate. The method comprises obtaining metrology data comprising single-wavelength parameter of interest values which were obtained using a respective different measurement wavelength; and determining said value for the parameter of interest from a stack sensitivity derived weighted combination of said single-wavelength parameter of interest values. Also disclosed is a method of selecting wavelengths for a measurement based on at least the derivative of the stack sensitivity with respect to wavelength.

Dependencies are inferred from the claim text.