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The pulsed laser deposition (PLD) technology was used to effectively create conductive nano and micro hafnium oxide with great purity and transparency for (HfO 2 ) nanofilms. In many optoelectronics devices and their applications, the presence of a high dielectric substance like a nano HfO 2 , between the metal contacts and the substrates was critical. We used the Pulsed Laser Deposition method to fabricate an Al/HfO 2 /p-Si Schottky barrier diode where the nanostructured HfO 2 films as an intermediate layer and varied substrate temperatures. The optical result reveals a high degree of transparency (93%). The optical bandgap of deposited HfO 2 films was observed to vary between 4.9 and 5.3 eV, with a value of roughly 5.3 eV at the optimal preparation condition. The morphology of the surface shows a high homogeneous nano structure with the average values of the roughness about (0.3 nm). With regard to substrate temperature, the produced factor ideality for fabricated diode was determined to be lowering and the associated values of the barrier height rose based on I-V characterization. With regard to substrate temperature, the produced factor ideality for fabricated diode was determined to be lowering and the associated values of the barrier height rose based on I-V characterization. The diode manufactured at 600 C, in particular, had a higher ideality factor value (n = 3.2).

Self-assembled TiO2 foam-like films, were grown by the water based Streaming Process for Electrodeless Electrochemical Deposition (SPEED). The morphology of the ∼1 µm thick films consists of a tangled ropy structure with individual strands of ∼200 nm diameter and open pores of 0.1 to 3 micron dimensions. Such films are advantageous for proposed perovskite solar cell comprising CH3NH3PbI3 absorber with additional inorganic films as contact and conduction layers, all deposited by SPEED. Lateral film resistivity is in the range 20 – 200 kΩ-cm, increasing with growth temperature, while sheet resistance is in the range 2 – 20 x 108 Ω/Sq. X-ray diffraction confirms presence of TiO2 crystals of orthorhombic class (Brookite). UV-vis spectroscopy shows high transmission below the expected 3.2 eV TiO2 bandgap. Transmittance increases with growth temperature.

In the last few decays, the fiber-optic was employed in the field of sensing because of its benefits in contrast to other types of sensors such as small size, easy to fabricate, high response, and flexibility. In this study, unclad single mode fiber-optic sensor is proposed to operate at 650 nm wavelength. COMSOL Multiphysics 5.1 finite element method (FEM) is used to design the sensor and tested it theoretically. The middle portion of the fiber cladding is removed and replaced by gold nanoparticles (Au NPs) of 50 nm thickness. Analytic layer of 3 μm thickness was immersed in different liquids in range of refractive index (RI) from 1.000281 to 1.39. These liquids are NaCl Deionized (DI) water solution, sucrose-Deionized (DI) water solution, and glycerol solution Deionized (DI) water. It was found that the highest obtained sensitivity and resolution are for glycerol-DI water solution with value of 3157.98 (nm/RIU) and 3.16 × 10–5 (RIU), respectively. Furthermore, it is easy to fabricate and of low cost. In experiments, pulsed laser ablation (PLA) was used to prepare Au NPs. X-ray diffraction (XRD) shown that the peak of the intensity grew as the ablated energy increased as well as the structure crystallization. Transmission electron microscopy (TEM) revealed an average diameter of 30 nm at the three ablated energies, while X-ray spectroscopy (EDX) spectrum has indicated the presence of Au NPs in the prepared solution. The photoluminescence (PL) and ultraviolet–visible UV–Vis transmission were used to study the optical properties of the prepared Au NPs. An optical spectrum analyzer was used to obtain the sensor's output results. It has shown that best intensity was obtained for sucrose which confined with theoretical results.