Design and characterization of micromachined piezoelectric acoustic flexural plate wave devices

Abstract

This paper presents a comparison of several piezoelectrically driven MEMS flexural plate wave (FPW) resonators, all with the electrical interfacing located on the top of the device and fully isolated from the fluidic interface and detection surface on the back of the device, in order to avoid mutual interference. The devices to be compared include devices designed to have wavelengths of 60μm and 100μm, and devices with and without a reflector grating. In general, the measured antisymmetric AO and symmetric SO modes of the devices in vacuum and air match well with values predicted by both analytical models and finite element analysis. The theoretical mass sensitivity of the FPWs is calculated to be 214.6cm2/g and is compared to an experimentally determined mass sensitivity for multiple modes.