Optoelectronic characterization of shape and deformation of MEMS accelerometers used in transportation applications

Recent technological trends based on miniaturization of mechanical, electromechanical,and photonic devices have led to the development of microelectromechanical systems (MEMS). Effective development of MEMS requires the synergism of advanced design, analysis, and fabrication methodologies, with quantitative metrology techniques for characterization of their performance, reliability, and integrity. We describe optoelectronic techniques for measuring, with submicrometer accuracy, shape and changes in states of deformation of MEMS accelerometers used in transportation applications. Using the display and data modes of the described optoelectronic techniques, it is possible to characterize MEMS. This characterization is performed during static and dynamic modes of operation of MEMS. To assure high accuracy of measurements, overlapping regions, i.e., tiles, of MEMS are analyzed and the data (tiles) are patched together to represent the entire component. Preliminary results indicate that the MEMS accelerometer considered in this study deforms 1.48 mum, under the loading conditions used, which represents nearly 50% of its functional dimension in the direction of deformation. (C) 2003 Society of Photo-Optical Instrumentation Engineers.