Thermally stimulated currents in PbTiO3thin films

Abstract
Using the Thermally Stimulated Current (TSC) method, the activation energy of trapping levels in sol-gel deposited lead titanate films was determined. Four levels were found in films annealed at 550 °C and 600 °C. Their activation energies are: E1 = 0.23 eV, E2 = 0.30 eV, E3 = 0.34 eV and E4 = 0.40 eV. For the films annealed at 650 °C only one level (E2) was observed. It was found that the TSC magnitude decreases if the same sample is subjected to several cycles of cooling and heating between 100 K and 373 K in vacuum. This suggests a “healing” of the traps, probably due to the desorption of some gaseous species from the surface of the ferroelectric thin film.