Tin oxide SnO2 thin films were deposited by sol gel method on glass substrates. The as-deposited thin films were then annealed at 550 °C for different time durations (15, 30, 60 and 120 min). Structural and morphological investigations were carried out on all samples by X-ray diffraction method and atomic force microscopy while optical properties were obtained with UV–Visible spectrophotometer. XRD patterns reveals that the samples possess polycrystalline with rutile structure of SnO2 without any secondary phase. AFM image showed that SnO2 thin films having a smooth surface morphology. The optical properties in the visible range showed that the deposited layers have a high transmission factor. The optical band gap energy varies in the range of 3.61–3.73 eV. Finally, ultraviolet (UV) detection properties of samples as an active layer in UV photodetector devices were investigated. Current-voltage characteristics of the SnO2 thin films are performed under dark and light environment, which show low dark current of 22.9 nA with a linear behavior and high current ration > 104 under 2 V applied voltage and 120 min as annealing time. Whereas, high photocurrent is observed for samples annealing for 30 min. Moreover, the transient photoresponse of the fabricated device is reported under different annealing times.

The influence of gate dielectric materials on the performance of a carbon nanotube field-effect transistor has been studied by a numerical simulation model. This model is based on a two-dimensional nonequilibrium Green’s function formalism performed with the self-consistent solution of the Poisson and Schrödinger equations. The device performance is investigated in terms of leakage current, on-state current, ION/IOFF current ratio, subthreshold slope, drain-induced barrier lowering, as well as transconductance, drain conductance, and intrinsic gate delay. This study is carried out over a wide range of dielectric permittivities at low temperatures ranging from room temperature down to 100 K.

In this work, sol—gel dip-coating technique was used to elaborate ZnO pure and ZnO/Al films. The impact of Al-doped concentration on the structural, optical, surface morphological and electrical properties of the elaborated samples was investigated. It was found that better electrical and optical performances have been obtained for an Al concentration equal to 5%, where the ZnO thin films exhibit a resistivity value equal to 1.64104 Ωcm. Moreover, highest transparency has been recorded for the same Al concentration value. The obtained results from this investigation make the developed thin film structure a potential candidate for high optoelectronic performance applications.