Development of dual-wavelength polarization interferometer for profile measurement of rough surface

This study proposes a dual-wavelength polarization interferometer for profile measurement of rough surfaces in semiconductor manufacturing. The system is based on a Michelson interferometer configuration that generates a synthetic wavelength, effectively resolves phase wrapping, and expands the measurable range of rough and rapidly changing surfaces. Integration with speckle interferometry suppresses high-frequency surface noise and improves fringe contrast. Experimental results demonstrate that the proposed method can effectively reconstruct the overall surface topography and suppress phase ambiguity even on challenging surfaces.