AlN/ZnO/Si structure - a packageless solution for acoustic wave sensors

The possibility to create a packageless structure for acoustic wave sensors applications based on AlN/IDT/ZnO/Si structure is investigated. The effect of thicknesses of AlN and ZnO thin films on structure performance was calculated by two dimensional finite element method. Theoretical predictions were confirmed by in-situ measurements of frequency and insertion loss that were performed during deposition of AlN layer together with AlN film thickness monitoring by interferential reflectometry method.