Thermally Stimulated Current Analysis of Defects in Sol--Gel Derived SrTa2O6 Thin-Film Capacitors

In this research, we demonstrated that defect states in sol--gel-derived SrTa 2 O 6 (STA) thin films can be detected by a thermal simulated current (TSC) technique. We also tentatively explained leakage current properties using these defect states. Similar defect states were found in STA thin films that were annealed at 700 and 800 °C by the TSC technique. Defects that caused the TSC peak at measurement temperatures of 130--150 °C showed higher trap densities in the 800 °C-annealed STA thin film. These defects were likely to be caused by diffused Ti, which mainly contributed to the larger leakage current in the 800 °C-annealed STA thin film. Oxygen-vacancy-related defect states were also clearly observed with the change in measurement atmosphere from air to vacuum.