Influence of a Tailored Oxide Interface on the Quality Factor of Microelectromechanical Resonators

Document Type


Publication Date



Piezoelectric microelectromechanical systems (MEMS) are used as sensors, actuators, energy harvesters, accelerometers, and communication modules. Aluminum nitride (AlN) is an especially attractive piezoelectric material because its fabrication process allows it to be integrated into semiconductor circuitry to deliver a fully integrated solution. Microelectromechanical resonators with AlN sandwiched between n-type silicon (Si) and top metal electrode with and without a silicon oxide layer are designed and fabricated. The effect of the oxide film is up to a fourfold increase in quality factor (Q) that is consistent from very high frequency (VHF) to super high frequency (SHF). This effect is demonstrated using thin plate bulk acoustic wave modes from 70–80 MHz using the second contour mode and first width extensional mode and from 9.5–10.5 GHz using high overtone thickness modes. To explore potential applications of AlN-transduced Q-enhanced MEMS devices in harsh environments, measurements from −200 °C to +200 °C are performed. The Q enhancement is persistent across a wide temperature range for both VHF and SHF resonators with the added oxide layer. Furthermore, AlN-on-Si resonators that have a comparable temperature coefficient of frequency to silicon carbide-based resonators in commercial applications are demonstrated.


© 2023 The Authors. Advanced Materials Interfaces published by Wiley-VCH GmbH.

The "Link to Full Text" on this page opens the full article (HTML) hosted at the Wiley Online Library. An open access PDF is available from that page.

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.



Source Publication

Advanced Materials Interfaces