Profile measurement system based on linnik-type interferometric microscope for visible-light region and infrared-light region

A profile measurement system consisting of linnik-type interferometric microscope, light source and cameras is developed based on white-light scanning interferometry extending from the visible-light region to the infrared-light region. Three-dimensional profiles of microstructures are obtained via a phase-stepping algorithm using a CMOS array camera for the visible-light region and an InGaAs CCD array camera for the infrared-light region. Errors of the measurement system along with extensive applications in MEMS device profile reconstruction of top surface, sidewall and internal structures are discussed in detail.