High G MEMS integrated accelerometer
- Sandia National Labs., Albuquerque, NM (United States). Integrated Micromechanics, Microsensors and CMOS Technology Dept.
This paper describes the design and implementation of a surface micromachined accelerometer for measuring very high levels of acceleration (up to 50,000 G). Both the mechanical and electronic portions of the sensor were integrated on a single substrate using a process developed at Sandia National Laboratories. In this process, the mechanical components of the sensor were first fabricated at the bottom of a trench etched into the water substrate. The trench was then filled with oxide and sealed to protect the mechanical components during subsequent microelectronics processing. The wafer surface was then planarized in preparation for CMOS processing using Chemical Mechanical Polishing (CMP). Next, the CMOS electronics were fabricated on areas of the wafer adjacent to the embedded structures. Finally, the mechanical structures were released and the sensor tested. The mechanical structure of the sensor consisted of two polysilicon plate masses suspended by multiple springs (cantilevered beam structures) over corresponding polysilicon plates fixed to the substrate to form two parallel plate capacitors. The first polysilicon plate mass was suspended using compliant springs (cantilever beams) and acted as a variable capacitor during sensor acceleration. The second polysilicon plate mass was suspended using very stiff springs and acted as a fixed capacitor during acceleration. Acceleration was measured by comparing the capacitance of the variable capacitor (compliant suspension) with the fixed capacitance (stiff suspension).
- Research Organization:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 453515
- Report Number(s):
- SAND-96-2075C; CONF-970324-4; ON: DE97004384; TRN: AHC29707%%85
- Resource Relation:
- Conference: SPIE meeting on smart structures and materials, San Diego, CA (United States), 3-6 Mar 1997; Other Information: PBD: [1996]
- Country of Publication:
- United States
- Language:
- English
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