Abstract
Studies of ZnO films which have been performed at Tohoku University are summarized to describe the important role of ZnO films in their application to surface acoustooptic devices on nonpiezoelectric substrates. The ZnO film has been confirmed experimentally as one of the most suitable materials for SAW transducers which can generate surface acoustic waves with power enough to attain the maximum diffraction efficiency in surface acoustooptic devices on nonpiezoelectric substrates in VHF and higher frequencies. It has also been confirmed to be useful as an optical waveguide which is suitable for use as the interaction medium in surface acoustooptic devices.