Characterization of aluminum nitride lamb wave resonators operating at 600°C for harsh environment RF applications

In this paper, aluminum nitride (AlN) Lamb wave resonators (LWR) operating in air from room temperature up to 600°C are demonstrated for the first time. To date, no AlN RF devices have been tested and characterized at extreme temperatures. This paper describes the design, fabrication and characterization of temperature compensated AlN Lamb wave resonators at 600°C. Temperature coefficients of frequency (TCF) of both uncompensated and compensated devices were measured. Quality factors against temperature were also recorded. This supports the use of piezoelectric AlN as the material platform for radio-frequency (RF) components and sensing applications in harsh environments.