Tuning of Barium Strontium Titanate (BST) Thin Film Materials Employing High Resistive Thin Indium Tin Oxide (ITO) Layer

The rapid growth of communication systems demands for wide tunable low loss microwave components. Barium strontium titanate (BST) voltage dependent permittivity has shown a great potential impact for the fabrication of frequency agile components. In this work, the indium tin oxide (ITO) high resistive thin layer is used as a bottom electrode to tune BST based structures such as parallel plate capacitor and CPW line. The tunability is reduced due to voltage drop in the ITO layer which exhibits a high dc resistance. The effect of using ITO thin layer in microwave device is explored.