Multi-Frequency Imaging with a CMOS Compatible Scandium Doped Aluminum Nitride PMUT Array

This work shows the benefits of using a CMOS compatible 9.5 % Scandium doped Aluminum Nitride Piezoelectric Micromachined Ultrasound Transducer array for multi-frequency imaging at 7 and 20 MHz. While the improvement of doping AlN for a single element with 9.5 % Scandium was proven before, we now show its capabilities in array configuration. By using two particular excitation modes of the MEMS array, multi-frequency imaging is enabled and demonstrated. Furthermore, the presented device is fabricated by the Silterra foundry and allows monolithic integration with supporting electronics. This opens the door to a next generation fully integrated solution with increased SNR.