Defect structure of strontium titanate thin films

The electrical and optical properties of deep-level defects in SrTiO3 thin films grown by organometallic chemical-vapor deposition were investigated. Transient photocapacitance spectroscopy was used to determine the deep-level defect structure. Metal/insulator/semiconductor diodes were used for these measurements. The dominant defects in the SrTiO3 consisted of a series of deep-level trapping states with energies in the range of Ev+2.4 to Ev+3.15 eV and a series of shallower traps near the conduction-band edge. The defect concentration ranged from 1014 to 1018 cm−3 in the as-grown films.