Transverse Spurious Mode Free SAW Resonators and Delay Line on GaN/Si with High Quality Factor

Abstract

This work presents a dummy finger structure for eliminating the transverse spurious mode on the GaN/Si surface acoustic wave (SAW) resonators. The fabricated resonators have a high quality factor, and the transverse spurious mode is effectively suppressed. A maximum quality factor of 81 77 at a resonant frequency $(f_{r})$ of 1.9173 GHz is obtained. Moreover, it is shown that the transverse spurious mode is independent of the propagation directions. A delay line with the dummy finger shows a minimum insertion loss of 16.44 dB. These results could pave the way for future intelligent lab-on-chip sensor applications.