Preparation and microstrutures of BSTO/MgO ferroelectric materials for phase shift

Abstract

Barium strontium titanate/magnesia (BSTO/MgO) ferroelectric material for phase shift was prepared by traditional solid phase synthesis. The phase distribution, microstructure and electric properties were investigated. The results show that no secondary phase appears in the composites and the dimension of grains distributes uniformly. With 50 wt% MgO content, the dielectric tunability reaches 17.5 % in the external DC field of 4 000 V·mm⁻¹ and the microwave loss at about 2.5 GHz is 8×10⁻³. Hence, it can be applied in tunable microwave phase shifters.

Keywords

barium strontium titanate/magnesia / ferroelectric material / phase shifter / dielectric

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