Characterization of the Current Mechanisms and Improved Leakage Current in Silver Doped Barium Strontium Titanate

Barium strontium titanate (BST) has gained attention as a high dielectric constant material for high capacitance density. The films are doped with silver, which can reduce the leakage current by an order of magnitude. In this report, we characterize the current mechanisms of doped and undoped BST films as space charge limited (SCL) transport and Schottky emission, respectively. Additionally, by extracting the trap density from the SCL flow, we show that the optimal doping concentration of silver for leakage reduction is calculated, which matches well with experimental data.