Robust dynamic spectroscopic imaging ellipsometer based on a monolithic polarizing Linnik interferometer

We describe a robust dynamic spectroscopic imaging ellipsometer (DSIE) based on a monolithic Linnik-type polarizing interferometer. The Linnik-type monolithic scheme combined with an additional compensation channel solves the long-term stability problem of previous single-channel DSIE. The importance of a global mapping phase error compensation method is also addressed for accurate 3-D cubic spectroscopic ellipsometric mapping in large-scale applications. To evaluate the effectiveness of the proposed compensation method for enhancing system robustness and reliability, a whole thin film wafer mapping is conducted in a general environment where various external disturbances affect the system.