The thickness effect on the electrical conduction mechanism in titanium oxide thin films

Electrical conduction mechanism and gas sensing properties of Pd-doped TiO2 films

“…Each oxygen vacancy gives two electrons in the titania conduction band, leading to a decrease of the film's electrical resistivity. The film's resistivity can also change, depending on the substrate nature, doping, or thickness of the TiO 2 film [14,15]. From Table 2, one can see that the room temperature resistivities are higher in ambient air than in vacuum, which agrees well with the results presented in ref.…”

“…Therefore, band bending is limited only to the surface region of the crystallite. Note that the electrical parameters (E b , L D , N d and l 2 ) obtained for the investigated samples, appear to be in reasonable agreement with the previous observations for various polycrystalline systems [14,15,19,20]. Thus, the approach of analyzing the data using the grain boundary model for the thermal activation of conductivity is valid for all the samples.…”

Enhancement of open-circuit voltage on organic photovoltaic devices by Al-doped TiO2 modifying layer produced by sol–gel method

“…Nevertheless, this phenomenon is limited by the oxygen adsorption that occurs, preferentially, in the grain boundaries [19], and decreases the electron mobility due to the oxygen efficiency in trapping electrons. Moreover, the growth of grain size decreases the grain boundaries [20] affecting the connection between grains [21] and, consequently, the charge mobility [22]. In the present work, it was observed that the TiO 2 and AlTiO 2 surface roughness increases not only with the post-done annealing temperature but also with the Al-dopant concentration.…”

Temperature dependent admittance spectroscopy of GaAs/AlGaAs single-quantum-well laser diodes (SQWLDs)

“…The temperature dependence of electrical characteristics of these devices has been widely investigated in the literature [35][36][37][38][39][40][41][42][43][44][45][46]. In our previous work [20], we have investigated temperature and voltage dependent current transport mechanisms in GaAs/AlGaAs single-quantum-well lasers using forward and reverse bias I-V measurements in the temperature range of 80-360 K. The analysis of the experimental I-V data of the studied structures indicated that the current-transport was controlled by the Thermionic Field-Emission (TFE) mechanism below 170 K and Thermionic Emission (TE) mechanism above 200 K. The high values of n especially at low temperatures showed that the conduction is controlled by TFE [7,20].…”