صالح حسون عبود العامري

In this study, the characteristics of metal–semiconductor–metal (MSM) photodetector based on a porous In0.27Ga0.73N thin film were reported. Nanostructured porous film was synthesized using the UV-assisted electrochemical etching technique. The formed pores were dissimilar in terms of shape and size. The effect of annealing in the range of 300–500 °C on Pt/In0.27Ga0.73N was investigated by I–V measurements. Schottky barrier height was at maximum value under 500 °C. The fabricated MSM photodetector shows photovoltaic characteristics in the green region of the electromagnetic spectrum. The device responsivity increased with increasing the bias voltage. Moreover, the rise and recovery times of the device were investigated at 10 mW cm−2 of a 550 nm chopped light. Finally, the sensitivity and quantum efficiency were also investigated.

In this study, nanoporous structures of In0.08Ga0.92N thin films were synthesized using anodic etching at various etching durations. The metal–semiconductor–metal photodetectors subsequentaly have been fabricated by depositing a high work function metal (Pt) on the thin films. Results show that the responsivity of the detector increased with increasing the etching duration to reach to the maximum value at 15 min. Moreover, the rise and recovery times of the device were investigated at 390 nm chopped light.

This study involves the synthesise of indium nitride (InN) nanoparticles at low temperature using a chemical method. Three samples were synthesised under different times to produce InN nanoparticle of high quality crystallinity. Results showed that the time of synthesise plays an important role for N enhancement in InN nanoparticle structure. The average diameters of cubic phase of InN nanoparticle were 16.5 nm. These properties support the use of InN as a potential material for the manufacture of highly efficient low cost solar cells.

In this paper, InGaN/GaN/AlN/Si (111) structure was grown using a plasma-assisted molecular beam epitaxy (PA-MBE) technique. The structural and optical properties of grown film have been characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), high resolution X-ray diffraction (HR-XRD) and photoluminescence (PL). Indium-mole fraction has been computed to be 0.27 using XRD data and Vegards law with high grain size and low tensile strain. Room-temperature photoluminescence revealed an intense peak at 534 nm (2.3 eV) related to our sample In0.27Ga0.73N.

Characteristics of MSM photodetector based on a porous In0.08Ga0.92N thin film were reported. Nanoporous structures of n-type In0.08Ga0.92N/AlN/Si thin films were synthesized by photoelectrochemical (PEC) etching at a ratio of 1:4 of HF:C2H5OH solution for 15min. The structural and optical properties of pre- and post-etched thin films were investigated. Field emission scanning electron microscope and atomic force microscope images showed that the pre-etched thin film has a sufficiently smooth surface over a large region and the roughness increased for porous film. Blue shift has been observed in photoluminescence emission peak at 300 K for porous sample. The photoluminescence intensity of the porous film indicated that the optical properties have been enhanced. A high work function metals (Pt and Ni) were deposited as a metal contact on the porous films. The rise and recovery times of the devices were investigated at 390nm chopped light. Finally, the sensitivity and quantum efficiency were also studied.

This work reports the growth of n-In0.27Ga0.73N/GaN/AlN epitaxial layer on Si(1 1 1) substrate by using plasma-assisted molecular beam epitaxy (MBE) and commercially obtained n-In0.08Ga0.92N/AlN. As-grown and commercial thin films were characterized by using field emission scanning electron microscopy, atomic force microscopy, and high-resolution X-ray diffraction. A high work function metal (Pt) was deposited as metal contact on the thin films, and the electrical characteristics of the films pre- and post-annealed at 500 °C were studied under 3 V. Results show that the electrical characteristics of post-annealed thin films are better than those of pre-annealed thin films.

This paper presents the morphology and structural studies of as-grown and porous In0.08Ga0.92N/AlN/Si thin films prepared by UV-assisted electrochemical etching under various etching durations. The morphology and structural properties of the as-grown and porous thin films were investigated. The atomic force microscope, field emission scanning electron microscope images, and X-ray diffraction measurements revealed that the films have smooth and uniform surface over a large region with wurtzite phase. The diffraction peaks of the post-etched samples were shifted to a higher angle region compared to the pre-etched sample indicating a change in composition of InGaN layer as In incorporation of the layer decreases, subsequently decreasing the lattice constant c (approach to cGaN) of the alloy with compressive strain.

This paper presents the growth conditions of In0.27Ga0.73N/Si(111) thin film with thickness of 110 nm prepared using plasma-assisted molecular beam epitaxy technique. Indium mole fraction of 0.27 was calculated using X-ray diffraction and Vegard’s law. Some ridges on the film were observed on the as-grown surface morphology. Furthermore, porous In0.27Ga0.73N structure was synthesized using UV-assisted electrochemical etching technique with various current densities. Formed pores were dissimilar in terms of shape and size because of changes in the etching current density. Crystallite size and the strain inside the film were calculated for both as-grown and porous In0.27Ga0.73N. The result shows that both crystallite size and compressive strain decreased with increasing current density. A slight blue shift of porous In0.27Ga0.73N regarding the wavelength of the as-grown film was observed at 554 and 553.1 nm by using photoluminescence measurements. Finally, a Raman phonon mode of A1(LO) at 625.6 cm-1 of the as-grown film was observed. However, a shift towards higher frequency was monitored in the porous In0.27Ga0.73N film.

In this work ,some electrical properties ( such as electrical conductivity ) and optical properties(such as refractive index ) of synthetic rubber solution in toluene with concentration ) ml gm (0.5 were measured at 30 co after irradiation the polymer with different doses of gamma ray by using 60 Co source with energy 1.25 MeV. The results show exchange effects of polymer-solvent molecules and polymer polymer macromolecules appear on increment in the value of refractive index, reflectance and Browster angle with the increasing gamma radiation dose , in contrast the electrical conductivity , molar conductivity and critical angle with increasing given dose .

In this work . The density , viscosity , electrical conductivity , molar conductivity , degree of dissociation and spectrum of absorbance were reported for polyisoprene solutions in toluene with different concentrations at 250C . Also , the average molecular weight ( Mv ) has been measured at the same temperature . The results show exchange interactions of polymer-polymer macromolecules and polymer-solvent molecules appeares on increment in the values of density , viscosity and absorbance with increasing polymer concentration . In contrast the electrical conductivity , molar conductivity and degree of dissociation decrease with increasing polymer concentration.