Investigation of High-Quality ZnO Film on Polycrystalline Diamond Wafer for Fabrication of High Frequency SAW Filter
ZnO films with piezoelectric properties were deposited on polycrystalline diamond wafers for high frequency surface acoustic wave filter applications by dc reactive magnetron sputtering. The influences of different sputtering pressures and substrate temperatures on the properties of ZnO films were discussed. Highly c-axis oriented, fine-grain ZnO films with excellent surface flatness (average surface roughness of 5.3 nm) and high resistivities (6.3×107 *·cm) have been obtained. Then Al films for interdigital-transducer were deposited on ZnO/diamond by electron evaporation, a 2.48 GHz longitudinally- coupled double-mode surface acoustic wave filter has been fabricated using the Al/ZnO film on diamond wafer.
Wei Pan and Jianghong Gong
X.B. Wang, J.J. Chen, D.M. Li, F. Zeng, F. Pan, "Investigation of High-Quality ZnO Film on Polycrystalline Diamond Wafer for Fabrication of High Frequency SAW Filter", Key Engineering Materials, Vols. 336-338, pp. 242-245, 2007