Piezoelectric devices enable many frequency control, filtering, and transducer functions, among which are: resonators in precision clock oscillators; front-end GPS filters for cell phones, sensors, and signal processors. Indeed, they are found embedded in all mobile voice, data, multimedia, and telecommunications systems in general, and provide timing in computers and actuation in many micro-electromechanical (MEMS) elements as well.

This seminar presents first a tutorial on the physics and circuitry of piezoelectric devices. The piezo-effect couples mechanically resonant structures to the capacitive drive, and leads naturally to representations in terms of analog equivalent circuits. These networks have the admirable property of depicting the workings of the devices in a manner that corresponds to the actual physics, permitting a clear understanding of the mechanisms involved, and where they are physically located.

For wireless applications, a premium is placed on small size and cost. Apart from these considerations, temperature and ruggedization are two of the biggest physical problems to be solved. For example, if a resonator must have a high Q, and still be able to withstand severe shocks, how do you get it to appear as if it were floating in thin air?

The second part of the seminar presents methods and materials that address these difficult constraints.

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