In this work, ZnS thin films have been deposited by developed laser deposition technique on glass substrates at room temperature. After deposition process, the films were annealed at different temperatures (200ºC , 300 ºC and 400ºC ) using thermal furnace.The developed technique was used to obtain homogeneous thin films of ZnS depending on vaporization of this semiconductor material by continuous CO2 laser with a simple fan to ensure obtaining homogeneous films. ZnS thin films were annealed at temperature 200ºC, 300 ºC and 400ºC for (20) minute in vacuum environment. Optical properties of ZnS thin film such as absorbance, transmittance, reflectance, optical band gap, refractive index extinction coefficient and absorption coefficient have been investigated. From this measurements, the bandgaps energies at room temperature, 200ºC , 300 ºC and 400ºC were found to be 3.7eV, 3.6eV, 3.4eV and 3.3eV respectively. The band gap decreased as the annealing temperature increased. The two point probe method was used for the investigation of electrical properties of the ZnS films such as current voltage characteristics and sheet resistance properties. From these measurements it was found that current decreased as the temperature increased, thus, the annealed films were found to be more resistance than the as-grown films.
Fiber Bragg Grating has many advantages where it can be used as a temperature sensor, pressure sensor or even as a refractive index sensor. Designing each of this fiber Bragg grating sensors should include some requirements. Fiber Bragg grating refractive index sensor is a very important application. In order to increase the sensing ability of fiber Bragg gratings, many methods were followed. In our proposed work, the fiber Bragg grating was written in a D-shaped optical fiber by using a phase mask method with KrFexcimer. The resultant fiber Bragg grating has a high reflectivity 99.99% with a Bragg wavelength of 1551.2 nm as a best result obtained from a phase mask with a grating period of 1057 nm. In this work it was found that the rota
... Show MorePurpose To test the effect of strategic Supremacy on strategic success A case study in Thi Qar Governorate, methodology/approach – this is a mandatory entry.
a case study was used and applied to the Department managers of Government of the province of Thi Qar, Research limitations/implications – It is clear that the strategic Supremacy variable is not being used effectively to achieve strategic success.
Practical implications – use strategic supremacy positively to Support for strategic success. implementing and monitoring ignorance of them in how to use thi
... Show More
(1)
In this work, the effect of laser energy on the properties of a calcium plasma generated by a Q-switched Nd: YAG laser at the fundamental wavelength was studied using spectroscopy. The Boltzmann plot and Stark broadening method were used to measure the main plasma parameters (electron temperature and electron density). The electron temperature ranged ( 0.169 -0.172 ) eV, the electron density ranged ( 2.10 – 2.63 ) for laser energy range of ( 400 – 700) mJ. Other basic plasma properties were also measured, including the Debye length, the number of particles in the Debye sphere, and the plasma frequency. Laser energy affects all plasma parameters, according to our results.
An assembled pulsed Nd:YAG laser-robot system for spot welding similar and dissimilar metals is presented in this paper. The study evaluates the performance of this system through investigating the possibility and accuracy of executing laser spot welding of 0.2 mm in thickness stainless steel grade AISI302 to 0.5 mm in thickness low carbon steel grade AISI1008. The influence of laser beam parameters (peak power, pulse energy, pulse duration, repetition rate, and focal plane position on the final gained best results are evaluated. Enhancement of the experimental results was carried by a computational simulation using ANSYS FLUENT 6.3 package code.
Indium Antimonide (InSb) thin films were grown onto well cleaned glass substrates at substrate temperatures (473 K) by flash evaporation. X-ray diffraction studies confirm the polycrystalline of the films and the films show preferential orientation along the (111) plane .The particle size increases with the increase of annealing time .The transmission spectra of prepared samples were found to be in the range (400-5000 cm-1 ) from FTIR study . This indicates that the crystallinity is improved in the films deposited at higher annealing time.
(Cu1-x,Agx)2ZnSnSe4 alloys have been fabricated with different Ag content(x=0, 0.1, and 0.2) successfully from their elements. Thin films of these alloys have been deposited on coring glass substrate at room temperature by thermal evaporation technique under vacuum of 10-5Torr with thickness of 800nm and deposition rate of 0.53 nm/sec. Later, films have been annealed in vacuum at (373, and 473)K, for one hour. The crystal structure of fabricated alloys and as deposited thin films had been examined by XRD analysis, which confirms the formation of tetragonal phase in [112] direction, and no secondary phases are founded. The shifting of main polycrystalline peak (112) to lower Bragg’s angle as compared to Cu2ZnSnSe4 angle refers to incorpora
... Show MoreThe electrical properties of thin film interdigital metalÂ
phthalocyanine - metal devices have been studied with regard to purity and electrode material . Devices utilising phthalocyanines ( H2 Pc ,
NiPc and CuPc) films with Au, Ag , Cu ' In and AI electrodes have been prepared with Pc layers fabricated from both as - supplied Pc powder and entrainer - subeimed material . The results indicate that
sublimed phthalocyanine with gold electrodes offers the best material
combination with regard to linearity , reversibility and reproducibility. Measurements of current &nbs
... Show MoreUtilizing first principles calculations within PW91 exchange-correlation method, we investigated a boron sheet that exhibits related electronic properties. The 2-dimensional boron sheet is flattened and has an atomic structure where the pair cores of every three ordered hexagons within the hexagonal network are loaded up by extra atoms, which saves the triangular lattice symmetry. The boron sheet takes possession of intrinsic metal properties and the electronic bands are comparable to the bands of the graphene that are close to the Fermi level. The real and imaginary parts of the dielectric function show a metallic or semiconductor behaviour, depending on the electric field direction.
(1)
Abstract:
The research aims to shed light on the Corona pandemic and its repercussions on the global economy in general, and on the activities of Iraqi economic units in particular. It also aims to show the impact of the auditor’s reporting on the effects of the Corona pandemic on economic units and its reflection on the quality of his reporting. To achieve the objectives of the research, the researcher prepared a questionnaire according to the five-point Likert scale and took into account in its preparation compatibility with the characteristics of the study community, and that the target community for this questionnaire are the economic units listed in the Iraq Stock Exchange that have complet
... Show More
(1)
Cadmium sulfide (CdS) nanocrystalline thin films are prepared onto ITO-glass and Si(111) substrates by chemical bath deposition method. The scanning electron microscope images showed that the CdS thin film onto Si substrate is more homogenous without vacancies. The XRD patterns of the CdS nanocrystalline thin film confirm that they have polycrystalline with cubic phase. Room temperature photoluminescence (PL) spectrum of the CdS nanocrystalline thin films shows emission band located at 502nm for CdS/Si sample while the CdS/ITO-glass thin films shows a broad emission band peaked at 505nm. The Raman spectra of CdS nanocrystalline thin films prepared onto Si and ITO-glass substrates contain two main peaks which are corresponding to the firs
... Show More