A layered SAW device based on ZnO/LiTaO/sub 3/ for liquid media sensing applications

Abstract

Surface Acoustic Wave (SAW) sensors comprising a zinc oxide guiding layer deposited on a 36/spl deg/-YX lithium tantalate substrate were developed. They were found to have greater mass sensitivity than other LiTaO/sub 3/ based SAW sensors, such as the -SiO/sub 2//LiTaO/sub 3/ configuration. In this paper, the fabrication of the ZnO/LiTaO/sub 3/ sensor is described and micro-characterisation of the deposited films is presented. Sensitivity of these devices to surface mass and dielectric perturbations is then presented, followed by an analysis of temperature stability.