Source: Sandia National Laboratories
Date: 7/1/95    Record No.: 10156
Contact: Marion Scott, 505-845-8146

Sandia's work in microsensor development includes acoustic, micro machine/micro electronics, fiber optics, and micro impedance techniques. They have their own complete CMOS IC fabrication capability in-house, as well as for gallium arsenide, enabling them to undertake unique development challenges, such as combining micro machined structures and associated electronics on an IC.

- A bulk quartz resonator can look at the condition of oil in situ. Other possible applications--monitor the state of charge of a Pb acid battery or the capacity of coolants.
- Surface acoustic wave devices coated with chemically sensitive films can sense chemical species in gas at parts per million by looking at resonance changes. With multiple coatings and using pattern recognition techniques it's possible to distinguish multiple species. Has been packaged in a down-hole tool for pollutant sensing.
-Hydrogen sensor on a chip uses special alloys that change their resistivity with maximum sensitivity to H2 concentration.
- Fiber optics offer another technique to sense a wide range of chemicals, such as hydrogen, mercury, SO2, chlorine, and various oxidants. The end of the fiber is coated with a thin chemically sensitive film that changes its reflectivity. CRADA underway with the JW Harley & Assoc to develop a H2 sensor for utility transformers.
- Micro impedance and capacitive sensors can measure physical features for manufacturing applications; e.g., detecting surface flaws in real time. This has been applied to textiles.
- Accelerometers measure vibration indicating structural changes. Sandia has developed a fiber optic/micro machine hybrid device.