User Manual

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shifted signal. Wide coverage of piezo film, with distributed electrode patterns, can be used to create
individual sensor/actuator pairs. Critical damping has been achieved with this piezo film laminate by
researchers at Massachusetts Institute of Technology and elsewhere.
The applications for this technology include the reduction in harmful vibrations in space-based
structures, fuselage for aircraft to cancel engine noise, quiet cars, quiet appliances, and a wide range of
other possibilities.
Sensors on Silicon
Piezoelectric polymers can be solution cast (spin coated) onto silicon, polarized in place, metallized in
pattern arrays, and interconnected with the integrated circuits on the chip. Minor modifications to wafer
processing make the silicon suitable for the piezo Polymer Sensor-On-Silicon (PSOS). Early work in
PSOS technology at Stanford University was frustrated by the need to adhesively bond thin sheet piezo
film onto silicon. The adhesive layer was difficult to apply to the silicon, introducing air bubbles,
wrinkles, nonuniform thickness layers, etc. The advent of new piezo polymer processing that eliminates
the adhesive makes the PSOS technology practical. R&D work at MSI and elsewhere includes the
development of pyroelectric arrays for infrared cameras, fingerprint readers, and thermal imaging
devices, ultrasound arrays for high resolution NDT and invasive medical imaging, and integrated
accelerometers for microminiature components.
Smart Skin
Piezoelectric film can both sense surface energy and can microdeflect the surface. These capabilities
may be of interest in active surfaces for sound cancellation, extension of laminar to turbulent flow
boundaries, etc. Considerable work is under way at university and government laboratories in these and
related applications.