Low-coherence interferometric absolute distance gauge for study of MEMS structures

  title={Low-coherence interferometric absolute distance gauge for study of MEMS structures},
  author={Wojciech J. Walecki and Kevin Lai and A. Pravdivtsev and Vitali Souchkov and Phuc Van and Talal Azfar and T. M. H. Wong and Siew Hock Lau and Ann Koo},
  booktitle={SPIE MOEMS-MEMS},
The most commonly employed tools for wafer thickness and topography metrology are based on capacitance method, which due to physical size of probes, and may not be suitable for direct measurement of multi-layer non-conductive wafers or Micro Electromechanical Systems (MEMS) structures. Recently developed that low coherence interferometry provides solution, which overcomes limitations of these methods. Selected MEMS applications including characterization of deep (high aspect) trenches and… 
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Interferometric Metrology for Thin and Ultra-Thin Compound Semiconductor Structures Mounted on Insulating Carriers
  • CS Mantech Conference,
  • 2004
Low Coherence Interferometry Based Metrologies for MEMs Manufacturing
  • 2004