Piezoelectric bimorph microphone built on micromachined parylene diaphragm

This paper describes a novel bimorph piezoelectric microphone built on a micromachined parylene diaphragm with two ZnO films of opposite c-axis orientations. Both the sensitivity and signal-to-noise ratio (SNR) of the bimorph parylene-diaphragm microphone have been demonstrated to be much higher than those of a conventional unimorph silicon-nitride-diaphragm microphone.