Transient response of BAW resonators

The high demand for die size reduction and higher power levels in front-end modules to accommodate growing complexity pushes bulk acoustic wave (BAW) devices further into the nonlinear regime. Therefore, in order to reduce or cancel them, it is important to determine how they manifest in film bulk acoustic resonator (FBAR). Lately, the idea that pulsing RF signals could be used to qualify FBAR filters while reducing the dissipated energy has been investigated, therefore the pulsed RF scheme enables the measurement of the electrical and thermal transient responses of BAW resonators with a special focus in the Duffing region. Nonlinear phenomena elicited within the thermal Duffing region are measured in both transient and steady state regime using thermal and acoustic imaging. In addition, a fully coupled 3D finite element model (FEM) of FBAR gives further insight into the observed transient dynamics.