학술논문

Metal-insulator transition in tin doped indium oxide (ITO) thin films: Quantum correction to the electrical conductivity.
Document Type
Article
Source
AIP Advances. 2017, Vol. 7 Issue 1, p1-7. 7p. 1 Chart, 5 Graphs.
Subject
*INDIUM tin oxide
*THIN films
*METAL-insulator transitions
Language
ISSN
2158-3226
Abstract
Tin doped indium oxide (ITO) thin films are being used extensively as transparent conductors in several applications. In the present communication, we report the electrical transport in DC magnetron sputtered ITO thin films (prepared at 300 K and subsequently annealed at 673 K in vacuum for 60 minutes) in low temperatures (25-300 K). The low temperature Hall effect and resistivity measurements reveal that the ITO thin films are moderately dis-ordered (kFl∼1; kF is the Fermi wave vector and l is the electron mean free path) and degenerate semiconductors. The transport of charge carriers (electrons) in these disordered ITO thin films takes place via the de-localized states. The disorder effects lead to the well-known ‘metal-insulator transition’ (MIT) which is observed at 110 K in these ITO thin films. The MIT in ITO thin films is explained by the quantum correction to the conductivity (QCC); this approach is based on the inclusion of quantum-mechanical interference effects in Boltzmann’s expression of the conductivity of the disordered systems. The insulating behaviour observed in ITO thin films below the MIT temperature is attributed to the combined effect of the weak localization and the electron-electron interactions. [ABSTRACT FROM AUTHOR]