A dynamic spectroscopic ellipsometer based on a one-piece interferometric polarization-modulation is described.

the proposed system can provide spectro-ellipsometric parameters Ψ(λ) and Δ(λ) with a real time speed of a few tens of milliseconds for 1,640-points spectra while maintaining high precision of less than 0.02 degrees. The ultrafast measurement capability enables the novel concept to be applied for a dynamic solution by which we can measure even the thin film thickness of moving samples dynamically.