Multislot coupled resonators formed on BST ferroelectric films as the basis of microwave tunable band-pass filters

Abstract

Microwave multislot transmission lines formed on (Ba, Sr)TO3-BST ferroelectric films were studied usingfull-wave analysis and resonator measurements. The BST films were grown on sapphire, MgO and alumina substrates in the process of RF sputtering. The multislot resonators formed on different types of BST films were measured at frequency similar to 30 GHz. The slot and multislot resonator topologies measured in rectangular waveguide had similar quality factor (100-120). The BST film dielectric characteristics were obtained: epsilon = 1100-1800; tan delta = 0.02-0.03. The coupled multislot structures were simulated to realize tunable band-pass filters of various tunability range, pass band and microwave losses in the band.