Preferred Language
Articles
/
IxZhh4sBVTCNdQwC-80u
Theoretical Simulation of Backscattering Electron Coefficient for SixGe1-x/Si Heterostructure as a Function of Primary Electron Beam Energy and Ge Concentration
...Show More Authors

Abstract: This study aims to investigate the backscattering electron coefficient for SixGe1-x/Si heterostructure sample as a function of primary electron beam energy (0.25-20 keV) and Ge concentration in the alloy. The results obtained have several characteristics that are as follows: the first one is that the intensity of the backscattered signal above the alloy is mainly related to the average atomic number of the SixGe1-x alloy. The second feature is that the backscattering electron coefficient line scan shows a constant value above each layer at low primary electron energies below 5 keV. However, at 5 keV and above, a peak and a dip appeared on the line scan above Si-Ge alloy and Si, respectively, close to the interfacing line. Furthermore, the shape and height of peak and dip broadening depend on the primary electron energy and incidence position with respect to the interfacing line. The last feature is that the spatial resolution of the backscattered signal at the interfacing line is improving by decreasing the primary electron energy (below 5 keV) and the shared element (Si) concentration. On the other hand, a poor compositional contrast has been shown at low primary electron energy below 5 keV. For energies above 5 keV, the spatial resolution becomes weak. These results can be explained by the behavior of the incident electrons inside the solid (interaction volume), especially at a distance close to the interfacing line and their chance to backscatter out of the sample. In general, a good compositional contrast with a high spatial resolution can be achieved at primary electron energy equal to 1 keV. Keywords: Monte Carlo model, Backscattering electron coefficient, Si-Ge/Si, Elastic scattering, Spatial resolution, Compositional contrast.

Scopus Clarivate Crossref
View Publication
Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Charge density distributions and electron scattering form factors of 19F, 27Al and 25Mg nuclei
...Show More Authors

An effective two-body density operator for point nucleon system folded with two-body correlation functions, which take account of the effect of the strong short range repulsion and the strong tensor force in the nucleon-nucleon forces, is produced and used to derive an explicit form for ground state two-body charge density distributions (2BCDD's) and elastic electron scattering form factors F (q) for 19F, 27Al and 25Mg nuclei. It is found that the inclusion of the two-body short range correlations (SRC) has the feature of reducing the central part of the 2BCDD's significantly and increasing the tail part of them slightly, i.e. it tends to increase the probability of transferring the protons from the central region of the nucleus towards

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Feb 24 2019
Journal Name
Iraqi Journal Of Physics
Modelling of electron trajectories inside SEM chamber concerning mirror effect phenomenon
...Show More Authors

A computational investigation is carried out to describe the behaviour of reflected electrons upon a charged insulator sample and producing mirror effect images. A theoretical expression for the scanning electron path equation is derived concerning Rutherford scattering and some electrostatic aspects. The importance of the derived formula come from its correlation among some of the most important parameters that controls the mirror effect phenomena. These parameters, in fact, are the trapped charges, incident angle and the scanning potential which investigated by considering its influences on the incident electrons. A pervious experimental operation requirements are adopted for operating the introduced expression. However, the obtained r

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Thu Dec 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of Annealing Temperature on the Optical Properties of the a-Ge: As Thin Films
...Show More Authors

a-Ge: As thin films have prepared by thermal evaporation teclmique, then they were annealing at various temperatures within the

range (373-473)  K.   The  result of  X-ray di ffraction spectrum  was showing  that  all  the  specimens  remained  in  amorphous structure before and after annealing  process. This paper studied the effect of annealing  temperature as  a  function of  wavelength on  the optical energy gap and optical constants for the a-Ge:As thin  films . Results have showed that there was an increasing in the optical energy gap

{Egopt) values with the in ,;rcasing of the annealing temperatures within

... Show More
View Publication Preview PDF
Publication Date
Fri Dec 15 2023
Journal Name
Iraqi Journal Of Laser
Numerical Simulation of Metasurface Grating to Function as Polarization Modulator in Quantum Key Distribution Systems
...Show More Authors

Polarization modulation plays an important role in polarization encoding in quantum key distribution. By using polarization modulation, quantum key distribution systems become more compact and more vulnerable as one laser source is used instead of using multiple laser sources that may cause side-channel attacks. Metasurfaces with their exceptional optical properties have led to the development of versatile ultrathin optical devices. They are made up of planar arrays of resonant or nearly resonant subwavelength pieces and provide complete control over reflected and transmitted electromagnetic waves opening several possibilities for the development of innovative optical components. In this work, the Si nanowire metasurface grating polarize

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 15 2023
Journal Name
Iraqi Journal Of Laser
Numerical Simulation of Metasurface Grating to Function as Polarization Modulator in Quantum Key Distribution Systems
...Show More Authors

larization modulation plays an important role in polarization encoding in quantum key distribution. By using polarization modulation, quantum key distribution systems become more compact and more vulnerable as one laser source is used instead of using multiple laser sources that may cause side-channel attacks. Metasurfaces with their exceptional optical properties have led to the development of versatile ultrathin optical devices. They are made up of planar arrays of resonant or nearly resonant subwavelength pieces and provide complete control over reflected and transmitted electromagnetic waves opening several possibilities for the development of innovative optical components. In this work, the Si nanowire metasurface

... Show More
Preview PDF
Crossref
Publication Date
Wed Feb 20 2019
Journal Name
Iraqi Journal Of Physics
Theoretical spectroscopic studies of potential energy curves and Fortran parabola for beryllium oxide molecule
...Show More Authors

    Theoretical spectroscopic  studies of  beryllium oxide has been  carried out, potential energy curves for ground states X1Σ+ and exited states A1Π , B1Σ+ by using two functions Morse and  and Varshni compared with experimental results. The potentials of this molecule are agreement with experimental results. The Fortrat Parabola corrcponding to  and branches were determind in the range 1<J<20 for the (0-0) band. It was found that for electronic transition  A1Π- X1Σ+  the bands head lies in  branche of  Fortrat p

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Jan 20 2024
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of Partial Substitution of Ge-S-Cd Alloys on the Density of Energy States
...Show More Authors

Five samples of the ternary alloy Ge-S-Cd were created using the melting point method, and the effects of partially substituting cadmium for germanium were determined. and partial substitution of germanium by cadmium was used to study the change in electrical conductivity. Electrical experiments were performed on Ge35-xS65Cdxternary alloy with x = 0, 5, 10, 15, and 20. It was discovered that the conductivity (σdc) rises with rising temperature in all samples under experiment. This confirms that the samples have semiconductor behavior. It has been observed that there are three regions of electrical conductivity in the electrical conductivity curve at low, moderate, and high temperatures. The pr

... Show More
View Publication
Crossref
Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
Characteristics of probing electrons behavior inside the chamber of scanning electron microscope
...Show More Authors
Abstract<p>The electron mirror phenomenon has been explored to describe the behavior of a probing electron trajectory inside the chamber of scanning electron microscope (SEM). This investigation has been carried out by means of the modulated mirror plot curve technique. This method is based on expanding sample potential to a multipolar form to detect the actual distribution of the trapped charges. Actually an experimental result is used to guiding results of this work toward the accurate side. Results have shown that the influence of each type of multipolar arrangement (monopole, dipole, quadruple, octopole … etc.) mainly depends on the driving potential.</p>
View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Fri Feb 08 2019
Journal Name
Iraqi Journal Of Laser
Effects of Laser Energy on n-Ge/p-SnS Hetrojunction Diode Detector in Different Environments
...Show More Authors

In the present work, heterojunction diode detectors will be prepared using germanium wafers as a substrate material and 200 nm tin sulfide thickness will be evaporated by using thermal evaporation method as thin film on the substrate. Nd:YAG laser (λ=532 nm) with different energy densities (5.66 J/cm2 and 11.32 J/cm2) is used to diffuse the SnS inside the surface of the germanium samples with 10 laser shots in different environments (vacuum and distilled water). I-V characteristics in the dark illumination, C-V characteristics, transmission measurements, spectral responsivity and quantum efficiency were investigated at 300K. The C-V measurements have shown that the heterojunction were of abrupt type and the maximum value of build-in pot

... Show More
View Publication Preview PDF
Publication Date
Wed Sep 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
Using simulation to estimate parameters and reliability function for extreme value distribution
...Show More Authors

   This study includes Estimating scale parameter, location parameter  and reliability function  for Extreme Value (EXV) distribution by two methods, namely: -
- Maximum Likelihood Method (MLE).
- Probability Weighted Moments Method (PWM).

 Used simulations to generate the required samples to estimate the parameters and reliability function of different sizes(n=10,25,50,100) , and give real values for the parameters are and , replicate the simulation experiments (RP=1000)

... Show More
View Publication Preview PDF
Crossref