Super-High-Frequency Two-Port AlN Contour-Mode Resonators for RF Applications

Matteo Rinaldi, University of Pennsylvania
Chiara Zuniga, University of Pennsylvania
Chengjie Zuo, University of Pennsylvania
Gianluca Piazza, University of Pennsylvania

Abstract

This paper reports on the design and experimental verification of a new class of thin-film (250 nm) super-high-frequency laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions to excite a contour-extensional mode of vibration in nanofeatures of an ultra-thin (250 nm) AlN film. In this first demonstration, 2-port resonators vibrating up to 4.5 GHz have been fabricated on the same die and attained electromechanical coupling, kt2, in excess of 1.5%. These devices are employed to synthesize the highest frequency MEMS filter (3.7 GHz) based on AlN contour-mode resonator technology ever reported.