Low-level effects in SBARs and their application to device optimisation

Solidly mounted bulk acoustic wave resonator (SBAR) filters for 1.9 GHz, 3 GHz, and 7.9 GHz have been made. For the 1.9 GHz filter a 1-D analytical electro-acoustic model combined with electrical parasitics is shown to accurately predict most features of resonator and filter behaviour. This paper describes how the analysis of these and other low-level effects in resonators allows material data to be determined and spurious modes and related acoustic loss mechanisms to be investigated.