Defects and Resistance Degradation of Sputtered Doped Lead Zirconate Titanate Thin Films

The resistance degradation of sputtered doped lead zirconate titanate thin film resulting from the lowering of the Schottky barrier height was identified by current-voltage characterization over degradation. In addition to migration of oxygen vacancies, potential hole trapping of lead vacancies was observed by Thermally Stimulated Depolarization Current measurements. Both defects were proposed to increase the effective positive space charge density near the interface depletion region along degradation and be responsible for the resulting resistance degradation. This manifestation of defects in the resistance degradation was found to be separated in degradation time and dependent on the wafer position.