Optical deflection measurement for characterization of microelectromechanical systems (MEMS)

Nonintrusive measurement of small out-of-plane motions of microscale structures is critical to the development of microelectromechanical systems (MEMS). This paper presents a low-cost deflection measurement system for MEMS structures based on a fiber optic displacement sensor. The system is demonstrated in the characterization of a microwave switch. The deflection system had a demonstrated sensitivity of 290 +-32 (mu)V/nm over a deflection range of 100 (mu)m. The calibration and linearity of the system are described, and the static and dynamic performance is compared to more elaborate systems.