The variation of electrical transport properties with thickness for ultrathin indium oxide films

Abstract

We have systematically investigated the electrical transport properties of a series of In2O3 films (with thickness t ranging from ∼4 to ∼45 nm) grown on yttrium stabilized ZrO2 single crystal substrates. Those tthinmathspace≳thinmathspace11.5nm films reveal metallic characteristics in electrical transport properties, and electron–electron interaction effects govern the low temperature behaviors of the resistivity. For the 6.3 and 3.7 nm thick films, the resistivities variation with temperature [ρfalse(Tfalse)] curves show insulator behaviors in the whole measured temperature range (2–300K). In addition, the two‐dimensional (2D) Mott type variable‐range‐hopping (VRH) dominates the temperature behavior of resistivity in the temperature range Tcross≲thinmathspaceTthinmathspace≲thinmathspace80thinmathspacenormalK, and a crossover to the 2D Efros–Shklovskii (ES) VRH occurs below Tcross. Our results are quantitatively consistent with the theoretical predications of the 2D Mott‐VRH and 2D ES‐VRH theories in the corresponding temperature regions.

Electrical conduction in gold nanoparticles embedded indium oxide films: a crossover from metallic to insulating behavior

“…It is a well-established fact that indium oxide (IO) can show characteristics of a heavily doped degenerate semiconductor to highly resistive semiconductor while remaining homogeneous and transparent [1][2][3][4]. Though this behavior has initially been attributed to the presence of oxygen vacancies, recent models proposed include consideration of a thin surface region with conductivity much higher than that of the bulk.…”