MEMS sensors and wireless telemetry for distributed systems

Conference · Sun Feb 01 04:00:00 EST 1998

OSTI ID:634103

Britton, Jr, C L; Warmack, R J; Smith, S F ^[1]

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1. and others

Selectively coated cantilevers are being developed at ORNL for chemical and biological sensing. The sensitivity can exceed that of other electro-mechanical devices as parts-per-trillion detection can be demonstrated for certain species. The authors are now proceeding to develop systems that employ electrically readable microcantilevers in a standard MEMS process and standard CMOS processes. One of their primary areas of interest is chemical sensing for environmental applications. Towards this end, they are presently developing electronic readout of a mercury-sensitive coated cantilever. In order to field arrays of distributed sensors, a wireless network for data reporting is needed. For this, the authors are developing on-chip spread-spectrum encoding and modulation circuitry to improve the robustness and security of sensor data in typical interference- and multipath-impaired environments. They have also provided for a selection of distinct spreading codes to serve groups of sensors in a common environment by the application of code-division multiple-access techniques. Most of the RF circuitry they have designed and fabricated in 0.5 {micro}m CMOS has been tested and verified operational to above 1 GHz. The initial intended operation is for use in the 915 MHz Industrial, Scientific, and Medical (ISM) band. This paper presents measured data on the microcantilever-based mercury detector. They also present design data and measurements of the RF telemetry chip.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 634103
• Report Number(s): ORNL/CP--96396; CONF-980308--; ON: DE98004053
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
DESIGN
DETECTION
INTEGRATED CIRCUITS
MEASURING METHODS
MERCURY
MONITORS
POLLUTANTS
READOUT SYSTEMS
TELEMETRY