Characterization of thin film BST tunable capacitors using a simple two port measurement technique

A simple two-port measurement technique was developed based on equivalent lumped element circuit model of capacitor using thin film barium strontium titanate (BST) material. This technique allows one to determine the loss contribution due to dielectric BST and conductor separately. The loss tangent of BST obtained is about 0.012 up to 10 GHz for a 0.24 pF capacitor. 2.4:1 tunability was achieved at the bias voltage of 15 V.