Dissipation of the charge injected into micro-areas at the sodium niobate film surface

Abstract

Dissipation of the charge injected into the 0.5 × 0.5 µm2 surface areas of [100] – oriented 500 nm-thick epitaxial NaNbO3 film was studied by Kelvin Probe Force Microscopy. The elliptical area of the electric potential spot dissipates during ∼4 ÷ 4.5 h via leakage through the film surface and substrate. At the final stage, a small negative surface potential clearly manifests itself in the places of the surface blocks as existed before injection. This inherent potential explains previously found unipolarity of this film. The charge diffusion coefficient and mobility of charge carriers are estimated.