Modeling and optimization of directive acoustical particle velocity sensors for ultrasonic applications

Acoustical particle velocity sensors for applications in the ultrasonic frequency range are investigated by means of finite element simulations. The operating principle of these devices is modulation of the heat transfer between pairs of parallel microwires, caused by the propagation of the acoustic wave. The sensing structure has been designed to be compatible with a commercial CMOS process followed by a simple post-processing procedure. An efficient enhanced-2D model has been used for the simulation of three different sensing structures. The dependence of the frequency response on geometrical parameters is investigated, demonstrating that one of the three analyzed structures can be actually optimized to obtain usable performances up to ultrasound frequencies.