Thin‐film zinc‐oxide microwave acoustic transducers have been formed successfully by vacuum deposition techniques upon a cooled substrate (−50°C) by evaporation of zinc with an oxygen beam. The films are hexagonal preferentially oriented withcaxis normal to the substrate. A device consisting of a ZnO film (1.9 &mgr;) deposited on a metallic film on a sapphire delay line had a one‐way conversion loss of 6 dB at 1.6 GHz with a large bandwidth indicating that zinc‐oxide thin films deposited by this method make good ultrasonic transducers at frequencies above 1 GHz.