Thickness dependence of leakage currents in high-permittivity thin films

Abstract

The leakage current through high-permittivity perovskite thin films in the nanometer range is of great technological interest because of the possible applications of these insulating films in future submicroelectronic devices such as dielectrics in Gbit dynamic random access memories or gate oxides in metal–oxide–semiconductor field-effect transistors. The experimental result of decreasing leakage current with decreasing thickness of the dielectric for the same externally applied field can be described by using a model combining thermionic emission at the electrode/dielectric interface and a low-mobility, high-permittivity dielectric with low-permittivity layers at the interfaces, the so-called dead layers.