Abstract: Systems and methods for acquiring measurements of structures of a bonded sample are disclosed. Such systems and methods may include determining a first registration measurement of a first registration structure and a first interface target structure of a first sample, and a second registration measurement of a second sample prior to coupling the samples together. Such systems and methods may include, after such a coupling of the samples, determining a third registration measurement of the coupled sample at least partially by measuring the first registration structure through the top face of the first sample. Such systems and methods may include acquiring an overlay measurement based on the first registration measurement, the second registration measurement, and the third registration measurement. Such systems and methods may include adjusting an inter-sample coupling recipe based on the overlay measurement, where the inter-sample coupling recipe may include a final bonding recipe.

Abstract: Methods and systems for measuring values of one or more parameters of interest, including changes in values of one or more parameters of interest, based on measured spectral differences are presented herein. A trained spectral difference based measurement model determines changes in the values of one or more parameters of interest based on a measure of differences in spectra measured before and after one or more process steps. In some examples, a measure of spectral difference is determined based on a difference in measured intensity, a difference in harmonic signal values, or a difference in value of one or more Mueller Matrix elements. A measure of spectral difference may be expressed as a set of difference values, a scalar value, or coefficients of a functional fit to difference values. A measure of spectral difference may be determined based on a weighting of spectral differences according to wavelength.