The study of structures based on nonstoichiometric SnO 2−x compounds, besides experimentally observed, is a challenging task taking into account their instabilities. In this paper, we report on single crystal Sn 3 O 4 nanobelts, which were successfully grown by a carbothermal evaporation process of SnO 2 powder in association with the well known vapor-solid mechanism. By combining the structural data and transport properties, the samples were investigated. The results showed a triclinic semiconductor structure with a fundamental gap of 2.9 eV. The semiconductor behavior was confirmed by the electron transport data, which pointed to the variable range hopping process as the main conduction mechanism, thus giving consistent support to the mechanisms underlying the observed semiconducting character.

Fermi level depinning in metal/Ge Schottky junction for metal source/drain Ge metal-oxide-semiconductor fieldeffect-transistor application J. Appl. Phys. 105, 023702 (2009)

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We report on transport measurements of individual Sn doped In2O3 nanowires. From these measurements we point out that spin–orbit and boundary scattering mechanisms seem to give a negligible contribution to the transport of electrons in these nanowires. In fact, these results can be extended to other oxide systems: the presence of a weak disorder arising from the random potential at the boundaries screen electrons away from the surface into the nanowire. Electrons travelling through the nanowire in inner conducting channels are not directly influenced by the surfaces and the boundary scattering is decreased. These findings were also supported by calculations of the electron distribution in the cross-section of the nanowires when some disorder is taken into account.

Aiming the understanding of how the application to devices is affected by the presence of oxygen in semiconductor nanostructures, Al/Ge-nanowires Schottky devices were fabricated without any previous treatment to remove the native oxide from nanowires' surface, originated during the growth process. Electronic transport properties of these devices were investigated and it was observed that interface states originated from the disordered oxide layer effectively pinned the Fermi level at the Ge surface, affecting Schottky barriers. Numerical calculations were made to complement this study agreeing with experiments.