Stiction Fault in MEMS Comb Drive Resonator

MEMS devices are vulnerable to various defect sources, such as point stiction, broken-beams, etch variation. Point stiction is the defect in which the movable parts of the device is stuck to the substrate or fixed parts at one or multiple point locations. Point stictions may affect the yield as well as the reliability of MEMS devices. Fault simulation is an effective way to study how the point stiction defects will affect the device yield and reliability. For point stiction defects, the occurrence and the location are random and cannot be precisely predicted. Such stochastic behavior can be better predicted with the Monte Carlo simulation. Monte Carlo simulation is a stochastic technique used to approximate the probability of specific outcomes by running multiple trial simulations using random numbers and probability statistics. In this paper, the ANSYS Monte Carlo simulation is used to simulate point-stiction defects in surface-micromachined MEMS comb resonator devices. The yield of MEMS devices is estimated based on the simulation results. The fault simulation in MEMS devices is essential to optimize the device performance and to improve the yield and reliability of MEMS devices