Silicon-integrated phononic bandgap crystal platform for sensors and signal processing elements: Theory and experiment

We report the theory, design methodology and experiment of an electrostatically actuated silicon-plate Phononic Bandgap (P
ⁿ
BG) crystal architecture. This architecture is a high-order distributed mechanical system comprised of a two-dimensional P
ⁿ
BG crystal which is truncated to finite periodicity and suspended from the substrate utilizing tethers. Electrostatic actuation mitigates the use of piezoelectric transducers and provides action at a distance type forces so crystal edges may be free standing for reduced anchor loss. A finite element method model of the P
ⁿ
BG crystal is developed. A P
ⁿ
BG crystal is fabricated in a SOI process. Preliminary verification of the architecture is obtained utilizing a laser-Doppler vibrometer.