Output pressure and pulse-echo characteristics of Capacitive Micromachined Ultrasonic Transducers as function of plate thickness

The energy transduction of a Capacitive Micromachined Ultrasonic Transducer (CMUT) depends on the movement of a flexible plate, which has a low mechanical impedance compared to its bulky piezoelectric counterpart. Consequently, the output pressure of a CMUT is generally lower. This limits the penetration depth, and thus the visualization of deeper structures in the body, as well as non-linear imaging such as tissue harmonic imaging. The objective of this work is to investigate how the output pressure and pulse-echo signal of a CMUT scales with the (silicon) plate thickness.