Periodically Poled Aluminum Scandium Nitride Bulk Acoustic Wave Resonators for Communications in the 6G Era

Abstract – Bulk Acoustic Wave (BAW) filter technologies find application in radio frequency (RF) communication systems for Wi-Fi, 3G, 4G, and 5G applications. In the beyond-5G (potential 6G) era, high frequency bands (>8 GHz) are expected to require resonators with high quality factor (Q) and electromechanical coupling (), once RF spectrum use in these bands increases. However, both Q and of traditional piezoelectric film based resonators, such as aluminum nitride (AlN) and aluminum scandium nitride (AlScN), decreases when scaled to high frequency (>8 GHz) while maintaining its impedance. In this talk, we present high frequency (~18 GHz) resonators constructed from AlScN periodically poled piezoelectric films (P3F) that achieve high quality factors and electromechanical coupling to show its potential for emerging RF communications in the beyond-5G era.