A model for the electric conduction in metal/poly-TiO₂/metal structure

Electrical characteristics of interfacial barriers at metal—TiO2 contacts

“…The contribution of internal point defectrelated ionic motions [47,48] and/ or those originating from the electrodes should also be taken into consideration. In particular for TiO 2 films, the Ti/TiO 2 /Ti stack appears to be very useful for these studies as it allowed for a detailed assessment of the core material controlled con duction mechanism [49,50]. The latter is supported by our results, as Ti was found to form ohmic or nonrectifying con tact when used both as a TE and as a BE.…”

Manipulating Electrical Properties of Nanopatterned Double-Barrier Schottky Junctions in Ti/TiOx/Fe Systems

“…27,28 The ionic transport in TiO 2 can also be present, like in the case of Ohmic Ti/TiO 2 /Ti junctions, for which the ionic migration is observed mainly at grain boundaries, while inner-grain ion movements are significantly slower. 29,30 The semiconductor/ferromagnetic systems are tested for the creation of a magnetically controlled junction with spindependent transport properties, 31,32 where the crucial factor for its electric characteristic is the quality of the interface between layers. 33 The nanopatterned surface induces the formation of surface states, leading to the change of the distribution of local electric fields and affecting the height of the Schottky barrier.…”

“…It is well established that the oxygen content at the interface between metal and titanium oxide is a decisive factor in terms of the barrier properties . For example, the Pt/TiO 2 /Pt junctions can display resistive switching properties due to the oxygen vacancy migration and redox reactions at the interface with the metallic layer which are responsible for the appearance of high and low resistance states. , The ionic transport in TiO 2 can also be present, like in the case of Ohmic Ti/TiO 2 /Ti junctions, for which the ionic migration is observed mainly at grain boundaries, while inner-grain ion movements are significantly slower. , …”

“…The tunneling could be either through the interface, 85 or in the case of polycrystalline samples, between magnetic grains. The latter requires magnetically disordered grain boundaries that act as a barrier, an effect described by the fluctuation-induced tunneling model 86 or the second-order tunneling process between neighboring grains through the intermediate state of grain boundaries, a model described by Lee et al 87 The disordered grain boundaries in the ATO/Fe junction can be formed through the ionic migration in titanium oxide-based junctions mentioned by Hossein-Babaei et al 29,30 The minimum MR observed for the nanoporous samples at 55 K (Figure 7 purple bars) is related to their magnetic properties. In order to investigate this hypothesis, we have performed zero-field-cooled/field-cooled magnetization measurements (Figure 9).…”