Abstract
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. We are now proceeding to develop systems that employ electrically readable microcantilevers in a standard MEMS process and standard CMOS processes. One of our primary areas of interest is chemical sensing for environmental applications. Towards this end, we 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, we 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. We 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 circuity we have designed and fabricated in 0.5 micrometers CMOS has been tested and verified operational to above 1 GHz. Our initial intended operation is for use in the 915 MHz Industrial, Scientific, and Medical band. This paper presents measured data on the microcantilever-based mercury detector. We will also present design data and measurements of the RF telemetry chip.
Original language | English |
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Pages (from-to) | 112-123 |
Number of pages | 12 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 3328 |
DOIs | |
State | Published - 1998 |
Event | Smart Structures and Materials 1998: Smart Electronics and MEMS - San Diego, CA, United States Duration: Mar 2 1998 → Mar 2 1998 |
Keywords
- CMOS
- MEMS
- Micro-cantilevers
- Sensors
- Telemetry
- Wireless