High Tunable BaTi x Zr 1-x O 3 Films on Dielectric Substrate for Microwave Applications.

In this study, the structural and microwave properties of BaTiZrO 3 films deposited on alumina substrate were investigated. The films were deposited by RF magnetron sputtering in Ar/O 2 ambient atmosphere. The research of the island films at the initial stages of the growth showed that the pyramidal type of growth prevails. It was demonstrated that as-deposited film is a BaZrTiO 3 solid solution with a deficiency of titanium compared to the target. The air annealing at temperatures of 1100-1200 °C leads to the formation of a well-formed crystalline solid solution of BaZr 0.3 Ti 0.7 O 3 with a predominant orientation ( h 00). The investigation of microwave parameters of the films fabricated at different conditions showed that the best performance with the tunability of 4.6 (78%), and the Q-factor of 18 to 40 at 2 GHz was achieved at annealing temperature of 1150 °C.