Super high frequency lithium niobate surface acoustic wave transducers up to 14 GHz

We report lithium niobate (LiNbO3) surface acoustic wave (SAW) transducers with the smallest linewidth and the highest resonant frequency. A record 30 nm wide, 200 nm period (λ0) nanofabricated metallic structure on non-conductive LiNbO3 enables a frequency exceeding 14 GHz. At higher frequencies, greater data throughputs and improved sensor sensitivity are enabled. A systematic study of SAW devices from λ0=200−800 nm is presented taking into account crystal orientation, device design, patterning strategies, and resonant modes. The device performance metrics such as frequency, g-factor, insertion loss, and coupling coefficient are measured in detail and these metrics are also found to exceed the results of other recent state-of-the-art devices, when compared.