Stress and Curvature in MEMS Mirrors

摘要

The goal of this study is to understand how to optimize the performance of micro-mirrors for a variety of optical microsystem applications. Our approach relies on a number of process variations and mirror designs to ultimately produce relatively large (500μm to mm-scale), smooth (for nm RMS), and flat mirrors (greater than 1m curvature). White-light interferometric measurements, and finite element models are discussed in support of these findings. Stress gradients and residual stresses have been measured for accurate modeling of micro-mirrors. Through this modeling study, we have identified relevant structural parameters that will optimize SUMMiT V~(TM)MEMS mirrors for optical applications. Ways of mitigating surface topography, print-through effects, and RMS roughness are currently being investigated.