Compact and/or MEMS-based gas-sampling sensors for analysis of battery offgassing Navy SBIR FY2010.1 Sol No.: Navy SBIR FY2010.1 Topic No.: N101-056 Topic Title: Compact and/or MEMS-based gas-sampling sensors for analysis of battery offgassing Proposal No.: N101-056-0448 Firm: Innovative Micro Technology 75 Robin Hill road Santa Barbara, California 93117 Contact: Jaquelin Spong Phone: (540) 331-4552 Web Site: www.imtmems.com Abstract: This Small Business Innovation Research Phase I SBIR project will prototype a MEMS-based gas sensor. The MEMS-based gas sensor uses a microfabricated photonic crystal to emit infrared light in a specific portion of the electromagnetic spectrum. The wavelength can be tuned by design to overlap an absorption band of methane, for example, to make a very small, very sensitive, very efficient detector of methane or other target gas. The MEMS-based approach also includes a microfabricated anti-reflective structure(SWARS), which uses microfabricated sub-wavelength features to reduce the effective index of refraction of the wafer material. The SWARS structure forms the lid which encapsulates the MEMS photonic crystal. Benefits: The approach described here may be used to produce MEMS-based gas sensors for virtually any gas having a well defined absorption band in the infrared. Accordingly, the techniques prototyped in Phase I may be readily adapted to make any of a number of other gas sensors, such as carbon dioxide, carbon monoxide, hydrocarbons, nitric oxide, nitrogen dioxide and sulphurous compounds. The microfabricated anti-reflective structures may be applied to any of a number of infrared devices, such as spectrometers, optical elements, and other infrared emitters and detectors. Furthermore, a plurality of MEMS photonic crystal can be made, each of which covers a different portion of the spectrum, to make a course but robust and inexpensive IR spectrometer. Because of the low cost involved in batch-fabricated micromechanical processing, the devices may have a cost advantage as well as improved shock and vibration, and low power consumption. Commercial applications include, for example, battery-powered methane sensors that may be mounted on miners'' helmets to warn of the presence of methane gas before deadly explosions occur, as well as numerous military applications. Return