Electrical Properties of SrTiO3 and SrTiO3/NiO Thin Films in Heterojunction Devices

摘要

The temperature-dependent electrical properties of solution-processed SrTiO3 (STO) and NiO/STO thin films in heterojunction devices were investigated at 50-150 degrees C. The band offsets were measured by XPS through the core level (CL) binding energy peak positions of Sr3d, Ti2p, Ni2p and O1s. Diode like features in current (I)-voltage (V) response indicated interface-limited Schottky emission as the calculated optical dielectric constants, 4.11 for STO and 6.26 for NiO. The interfacial potential barrier height at zero bias was similar to 0.30 eV for both Si/Pt/STO/Pt and Si/PYSTO/NiO/Pt assemblies, indicating that reduction of leakage current owes it to the large conduction and valence band offset of similar to 2.02 and 2.17 eV, respectively.