Reduced charge fluctuations in individual SnO2 nanowires by suppressed surface reactions

Abstract

The interactions between metal oxide nanowires and molecular species can significantly affect the electrical properties of metal oxide nanowires. A passivation process is needed to stabilize the electrical characteristics, regardless of the environmental changes. Herein, we investigated the passivation effects of a polymethyl methacrylate (PMMA) layer on SnO2 nanowire (NW) field-effect transistors (FETs). As a result of the PMMA coating, the electrical properties of the SnO2 NW FETs improved. The electrical noise behavior in both non-passivated and passivated devices can be described with the carrier number fluctuation model associated with the trapping and the release of charge carriers at the surface. The non-passivated devices exhibited higher noise levels than those of the passivated devices. These results demonstrate that surface passivation can lead to the suppression of dynamic responses (electron trapping/release events and scattering fluctuations).