XBAW, An Enabling Technology for Next Generation Resonators and Filter Solutions for 5G and Wi-Fi 6/6E/7 applications (Invited)

• Published in: 2022 International Electron Devices Meeting (IEDM) pp. 16.1.1 - 16.1.4
• Main Authors: Vetury, Ramakrishna, Kochhar, Abhay S., Shealy, Jeffrey B.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 03.12.2022
• Subjects: AlN; AlScN; BAW; Filtering; Piezoelectric films; Q-factor; Resonator filters; Resonators; RF Filters; Si-MEMS; Silicon; Wi-Fi; WiFi 6; WiFi 6E; WiFi 7; Wireless fidelity; XBAW
• ISSN: 2156-017X
• DOI: 10.1109/IEDM45625.2022.10019537

We report XBAW, a bulk acoustic wave (BAW) manufacturing technology using a unique transferred substrate process for next generation 5G and Wi-Fi 6/6E/7 application. This work reports performance metrics of resonators and filters built from high quality Aluminum Scandium Nitride (AlScN) piezoelectric films of varying Sc concentrations grown on 150mm < 100 > silicon substrates. Bulk acoustic wave resonators were fabricated using XBAW technology ranging from 5 GHz to 7 GHz and using varying Sc concentrations. The trade space between acoustic Q factors and \text{k}_{t}^{2} and dependence on Sc concentration is presented. We report multiple distinct filtering solutions for WiFi 6/6E/7 systems enabling optimal and flexible system utilization of available 160 MHz channels in UNII bands 1 through 8, including a diplexer with 50 dB of isolation between channels. These results show XBAW capability to extract maximum resonator FOM from AlScN, enabling optimal design of high-performance filters.