Authors: L.A. Starman_Jr., E.M. Ochoa, J.A. Lott, M.S. Amer, W.D. Cowan and J.D. Busbee
Affilation: Air Force Institute of Technology, United States
Pages: 314 - 317
Keywords: Raman spectroscopy, MEMS, MUMPs, Residual stress, stress characterization
We characterize and measure the pre-released residual stress levels in polysilicon Micro-Electro-Mechanical Systems (MEMS) microbridges using micro-Raman spectroscopy. Raman spectroscopy is nondestructive, fast, and provides the potential for in situ stress monitoring during fabrication. Residual stress from the deposition process can have profound affects on the functionality and reliability of MEMS devices. Several post-fabrication processes are available (ion implantation, diffusion, and anneals) which can in°uence the residual stress in thin films. We performed a series of phosphorous implants to quantify the in°uence of doping and anneals on the residual stress levels in MEMS devices. This experiment demonstrates the effective use of Raman spectroscopy to monitor and provide information to help control or in°uence the residual stress in MEMS structures [1-4].