deposited BaZr0.35Ti0.65O3 (BZT) thin films have been investigated. The films were of single perovskite phase with strong (100) preferred orientation when it were grown on LaNiO3 buffered Pt/Ti/SiO2/Si substrates using a diluted precursor solution. Variation of the precursor solution concentration resulted in a different microstructure and, in turn, affected the dielectric properties of the sol-gel deposited films. The BZT thin film showed a very stable and highly insulative characteristic against applied field. This work clearly reveals the highly promising potential of BZT compared with barium strontium titanium films for application in tunable microwave devices. (C) 2003 Elsevier B.V. All rights reserved.