Low Temperature Growth of Piezoelectric Films by RF Reactive Planar Magnetron Sputtering

Abstract

Piezoelectric films of ZnO, AlN and KLN have been fabricated by rf planar magnetron sputtering. A single-drystalline AlN film has been grown epitaxially onto a basal plane sapphire substrate, and a c-axis oriented AlN film has also been grown on a glass or metal-film substrate at substrate temperatures as low at 50°C to 500°C. Because of this low substrate temperature, AlN films have become available for the first time to bulk wave transducers, SAW transducers with the IDT's between AlN films and substrates, SAW transducers on low melting point material, and piezoelectric resonators separated from their substrates.