Premium
Low temperature thermally stimulated current characterization of nanoporous TiO 2 films
Author(s) -
Bruzzi Mara,
Mori Riccardo,
Carnevale Ennio,
Scaringella Monica,
Bogani Franco
Publication year - 2014
Publication title -
physica status solidi (a)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.532
H-Index - 104
eISSN - 1862-6319
pISSN - 1862-6300
DOI - 10.1002/pssa.201330608
Subject(s) - nanoporous , thermal conduction , conductivity , materials science , condensed matter physics , atmospheric temperature range , substrate (aquarium) , characterization (materials science) , colloid , electrical resistivity and conductivity , chemical physics , thermodynamics , nanotechnology , chemistry , composite material , physics , oceanography , geology , quantum mechanics
Nanoporous films of TiO 2 have been obtained by deposition on an alumina substrate of a commercial colloid and Au contacts have been put on surface for in‐plane conductivity measurements. Samples have been characterized by means of a series of sequential thermally stimulated currents scans, from nearly liquid He temperature up to 200 K, in order to get information on: conduction mechanisms, distribution of intragap density of states and recombination times of free an localized carriers. A model for hopping conductivity has been considered to properly take into account of localized states filling; it has been used to fit the experimental data, without a‐priori assumptions on the nature of the conduction mechanisms. It is found that hopping conductivity prevails over free‐carrier, in quasi‐equilibrium regime, in the investigated temperature range.