Conduction mechanisms in sputtered Ta2O5 on Si with an interfacial SiO2 layer

Abstract
The temperature dependence of leakage in sputtered Ta2O5 films (10–30 nm) on Si substrates with an interfacial SiO2 layer has been studied for temperatures between –50 and +100 °C and for electric fields between 0 and 2 MV/cm. The activation energy of leakage and the current‐voltage relationships have been used to identify various high field conduction mechanisms such as Poole–Frenkel transport at high temperatures and field emission at low temperatures. At low fields and intermediate temperatures, electronic hopping conduction leading to space‐charge‐limited flow at high current densities has been observed.