Imaging of acoustic fields in bulk acoustic-wave thin-film resonators

By using an atomic-force-microscope-based technique, we image the vibration of high-frequency, bulk-mode, thin-film resonators. Our experimental techn ique is capable of monitoring the vibration of these devices over a broad f requency range, from 1 MHz to beyond 10 GHz, allowing us to obtain quantita tive measurements of the piezoelectric properties of thin-film materials in that frequency range. This technique allows us to map the complex vibratio n modes of a new generation of high-frequency bulk piezoelectric resonators , revealing the presence of vibration patterns of very different characteri stic lengths. (C) 2000 American Institute of Physics. [S0003-6951(00)00726- 9].