Preparation and Study of Cadmium Oxide Doped Gallium Oxide Thin Films and application of Gas Sensor

In this paper, the structure and optical properties of pure cadmium oxide films, and doped with gallium oxide have been achieved, the films were deposited on glass and silicon substrates, with different ratios (1,3,5,7)% via spry pyrolysis method, at the substrate temperature of ̊ C300. XRD results showed that all prepared films had a cubic polycrystalline structure, with preferred orientation of (111) for cadmium oxide. Surface morphology was studied using atomic force microscope (AFM), the grain size of the thin films was about 105.42-69.07 nm, with surface roughness is about (3.32-0.901) nm and root mean square (RMS) (3.97-1.05) nm for cadmium oxide films. The optical properties were studied using UV-VIS spectroscopy at wavelength (300-1100 nm), It was observed that the value of transmittance increases when the gallium doping are increasing and the films have a direct energy gap about (2.3-4) eV that increases with the increase in gallium concentration. Sensitivity properties of pure cadmium oxide films, and doped with gallium oxide was deposed on silicon substrates of NO2 gas at different operation temperatures was found that the films of CdO doped with Gallium oxide on silicon substrate has greater sensitivity than the films than the undoped and that the doping has improved the sensitivity of the membranes CdO

The correlation of blue shift of photoluminescence and morphology of silicon nanoporous

Porous silicon with diameters ranging from 6.41 to 7.12 nm were synthesized via electrochemical etching by varied anodization current density in ethanoic solutions containing aqueous hydrofluoric acid up to 65mA/cm2.The luminescence properties of the nanoporous at room temperature were analyzed via photoluminescence spectroscopy. Photoluminescence PL spectra exhibit a broad emission band in the range of 360-700 nm photon energy. The PL spectrum has a blue shift in varied anodization current density; the blue shift incremented as the existing of anodization although the intensity decreased. The current blue shift is owning to alteration of silicon nanocrystal structure at the superficies. The superficial morphology of the PS layers consists of unified and orderly distribution of nanocrystalline Si structures, have high porosity around (93.75%) and high thickness 39.52 µm

Impact of ablation time on Cu oxide nanoparticle green synthesis via pulsed laser ablation in liquid media

Large-scale commercial production of nanoparticles via efficient, economical, and environmentally friendly methods is a challenging endeavour. The laser ablation method being a green and potential route of nanoparticles synthesis can be exploited to achieve this end. In this work, we report the ablation of a copper target submerged in distilled water by pulsed Nd:YAG laser. The influence of ablation time on the structure and optical properties of grown copper oxide nanoparticles are studied. Such nanoparticle composition and structure is determined by X-ray diffraction (XRD), Fourier transform infrared, and Raman analyses. Results from transmission electron microscopy images established that synthesised nanoparticles are a spherical shape with average sizes of 24–37 nm. Fluorescence spectra revealed the enhancement of nanoparticle concentration and reduction in the sizes with increasing ablation time, where the optimum ablation time is demonstrated to be 60 min. Photoluminescence spectra exhibited a prominent visible peak (green), which blueshifted from 542 to 537 nm, confirming the shrinkage of copper oxide particle size at higher ablation time. The XRD pattern showed that the prepared nanoparticles possess a single phase of monocline cupric oxide nanostructure

Photophysical performance of radio frequency sputtered Pt/n-PSi/ZnO NCs/Pt photovoltaic photodetectors

The effect of the annealing temperature on the photoelectrical properties of the nanoporous silicon/zinc oxide nanocrystallites-based (Pt/n-PSi/ZnO NCs/Pt) photodetector was investigated. Different morphologies of 3D ZnO were synthesized onto the n-PSi substrates via radio frequency (RF) sputtering in the absence of a catalyst. The synthesis of ZnO NCs was controlled by varying the growth temperature between 600–700 °C and 800–900 °C. The effect of the synthesis temperature on the structural, morphological, and optical properties of the n-PSi/ZnO NCs was systematically studied using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), atomic force microscopy (AFM), and photoluminescence spectroscopy (PL) techniques. The roughness was found to be dependent on the anodization current density. The optimal n-PSi/ZnO NCs-based metal-semiconductor-metal UV detector (MSM) was fabricated at 700 °C. The fabricated device showed a high sensitivity of 1007.14, an internal photoconductive gain of 11.07, and a responsivity of 5.99 A/W with a low dark current when illuminated with 380 nm light (1.55 mW/cm2) at +5 V bias voltage. In addition, the response and recovery times were determined to be 0.34 and 0.22 s, respectively. This approach offers a cost-effective substrate and simple synthesis method to improve the growth of the n-PSi/ZnO NCs and demonstrates the successful fabrication of nanoscale photodetectors with potential application in nano-optics devices

Germanium Semiconductor Nanoparticles Quantum Dot Size dependant for Solar Cell Antireflection Coating Applications

Nanostructured germanium semiconductor optical properties such as energy gap and refractive indexes as function of particle size were investigated. Single-layer antireflection coatings at a quarter wave thickness at λo in the spectrum range of (400-700 nm ) was theoretically designed,when particle size is between (3.6–80 nm) and (Si) as substrate. MATLAB language programs with version of 7.11.0 were used in this study to describe the reflectance as a function of particle size, refractive indexes, energy gap and the wavelength at normal and oblique incidence angle which are depending on Brus model and Characteristic Matrix theory. The result sowed that the coating design (Air/Nano Ge/Si) showed minimum reflectivity value of (0.1623%) at the incident angle of 0° with wavelength of 550 nm and particle size of (Ps=4.4 nm)

Preparation and Study of Cadmium Oxide Doped Gallium Oxide Thin Films and application of Gas Sensor

In this paper, the structure and optical properties of pure cadmium oxide films, and doped with gallium oxide have been achieved, the films were deposited on glass and silicon substrates, with different ratios (1,3,5,7)% via spry pyrolysis method, at the substrate temperature of ̊ C300. XRD results showed that all prepared films had a cubic polycrystalline structure, with preferred orientation of (111) for cadmium oxide. Surface morphology was studied using  atomic force microscope (AFM), the grain size of the thin films was about 105.42-69.07 nm, with surface roughness  is about (3.32-0.901) nm and root mean square (RMS) (3.97-1.05) nm for cadmium oxide films. The optical properties were studied using UV-VIS spectroscopy at wavelength (300-1100 nm), It was observed that the value of transmittance increases when the gallium doping are increasing and the films have a direct energy gap about (2.3-4) eV that increases with the increase in gallium concentration. Sensitivity properties of pure cadmium oxide films, and doped with gallium oxide was deposed on silicon substrates of NO2 gas at different operation temperatures was found that the films of CdO doped with Gallium oxide on silicon substrate has greater sensitivity than the films than the undoped and that the doping has improved the sensitivity of the membranes CdO

FABRICAT & STUDY CU0.5IN0.5S2 THIN FILMS COMPOSITE PREPARED BYPYLORYSIS SPRAY METHOD.

Thin film of Cu0.5In0.5S2 has been prepared by spray pyrolysis on different substrate of silicon and glass slides (25mm ×25mm) substrate at temperature (Ts) of 300 ±10oC . The thickness of thin films is 500 ±20nm. The morphology of the prepared film showed asmooth formationwith small grain sizes overall the entire surface.This indicates that the formation of crystalline compounds. The optical characteristics of thin film have been investigated by UV-VIS spectrophotometer in the wavelength range (300 -1000nm ) . The film has a direct allows electronic transition with the optical energy gap ( Eg ) of 2.9 eV . The broadening of the band gap energy occurs with the decrease in the crystallite size. The papered film revealed a good light trapping of wide wavelength spectrum. This means the film is promising in optoelectronic applications. The electrical properties were investigated using Hall measurements techniques; the result provides an evidence of p-type