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Article
Structural Properties of Semiconducting Nanostructures Prepared by DC Plasma Reactive Sputtering Method

Author: Noor I. Naji
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2014 Volume: 10 Issue: 3 Pages: 41-44
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, semiconducting nickel oxide (NiO) nanostructures were prepared by reactive dc plasma sputtering method. Magnetron was employed at the cathode to prepare these nanostructures and show the advantage of such device in the production of highly pure nanostructures. The sputtered nickel atoms were sputtered and oxidized in presence of oxygen in the Ar:O2 gas mixture of 4:1 ratio. Employment of magnetron results in formation of NiO only in the final samples according to the XRD analysis, increase the roughness and hence surface area of the produced NiO nanostructures, and finally decrease the particle size of NiO nanoparticles lower than 100nm. These improvements in the structural properties of the produced NiO make these nanostructures good candidates for specific applications, such as photodetectors, solar cells and electrochromic smart windows.


Article
Preparation of Highly Pure Nanostructures by Reactive DC Magnetron Sputtering Technique
تحضير تراكيب نانوية عالية النقاوة باستخدام تقنية الترذيذ التفاعلي المستمر

Authors: Firas J. Kadhim --- Oday A. Hammadi --- Mohammed K. Khalaf --- Bahaa T. Chiad
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 3 Pages: 27-34
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, metal oxide and nitride nanostructures were prepared by reactive dc magnetron sputtering technique. These nanostructures were synthesized from metal oxide such as NiO and nitride such as Si3N4 for functional materials applications. The prepared nanostructures were diagnosed by x-ray diffraction (XRD) patterns and Fourier-transform infrared (FTIR) spectroscopy. The results showed that the prepared nanostructures are highly pure, which is ascribed to the featured characteristics of magnetron sputtering technique for such purposes.


Article
Preparation and Characterization of Silicon Dioxide Nanostructures by DC Reactive Closed-Field Unbalanced Magnetron Sputtering

Authors: Mohammed A. Hameed --- Zahraa M. Jabbar
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 4 Pages: 13-18
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, silicon dioxide nanostructures were prepared by a reactive closed-field unbalanced magnetron dc plasma sputtering technique. The target of p-type silicon was sputtered in presence of argon-oxygen gas mixture used for plasma generation and oxidation of silicon sputtered atoms. The x-ray diffraction patterns showed that only distinct peak corresponding to the crystal plane of (101) was observed with reasonable intensity. This is typical behavior of nanostructures. The scanning electron microscopy of the prepared samples showed that certain gas mixtures can produce the smallest particles with high probability for large grains to grow. Uniform distributed particles could be obtained using different mixtures. The energy-dispersive x-ray spectroscopy showed that only silicon and oxygen have appeared in the final sample with different weight percentages depending on the mixing ratio of the argon and oxygen gases. The SiO2 prepared in this work are very good candidates to be employed in random gain media as scattering particles.


Article
Preparation and Characterization of Silicon Nitride Nanostructures Prepared by DC Reactive Sputtering Technique with Novel Design of Closed-Field Unbalanced Dual Magnetron Assembly

Authors: Firas J. Kadhim --- Mohammed K. Khalaf --- Oday A. Hammadi
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2017 Volume: 13 Issue: 3 Pages: 3-12
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, novel design of closed-field unbalanced dual magnetrons system was employed in a DC reactive sputtering system to prepare silicon nitride nanostructures. Two types of silicon wafers (n- and p-type) were sputtered in presence of nitrogen gas to deposit nanostructured silicon nitride thin films on glass substrates. The prepared nanostructured were polycrystalline with six dominant crystal planes: (101), (110), (200), (232), (301) and (321). The surface roughness of the sample prepared at inter-electrode distance of 4cm was higher than other samples prepared at smaller or larger distances and the average and R.M.S roughness were 0.777 and 1.03 nm, respectively. The nanoparticles of minimum size of 30nm were formed and recognized as individual accumulated particles. Two bands of significant absorption were observed around 960 and 1086 cm-1, those are attributed to the Si-N-Si vibration mode in Si3N4 molecule. An absorption peak was observed at 389nm, which is attributed to the quantum size effect of nanostructures. The refractive index of the prepared Si3N4 samples was determined to be 1.38-2.1 and the energy band gap was ranging in 5.1-5.2 eV. The energy band gap was found to increase with decreasing thickness of the prepared film. The wide energy band gap of Si3N4 nanostructures makes them good candidate, as similar as AlN, BN and GaN, for power electronics and optoelectronics operating at high temperatures.


Article
Effect of Gas Mixing Ratio on Energy Band Gap of Mixed-Phase Titanium Dioxide Nanostructures Prepared by Reactive Magnetron Sputtering Technique

Authors: Esraa A. Al-Oubidy --- Firas J. Al-Maliki
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2018 Volume: 14 Issue: 4 Pages: 19-23
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, a homemade dc closed-field unbalanced reactive magnetron sputtering system was used to prepare high-quality and highly pure titanium dioxide nanostructures. The operation parameters of the magnetron sputtering system were optimized to prepare TiO2 nanostructures as thin films on glass substrates. These films were characterized by x-ray diffraction, scanning electron microscopy, atomic force microscopy and Fourier-transform infrared spectroscopy. Both anatase and rutile phases were identified. From the UV-visible spectroscopy, the indirect energy band gap was determined to be 3.30-3.38 eV. The mixing ratio of argon and oxygen (Ar:O2) gases was found very important to control the structural and optical characteristics of the prepared nanostructures.


Article
Structural Characteristics of Silicon Nitride Nanostructures Synthesized by DC Reactive Magnetron Sputtering

Authors: Baraa K. Nasser --- Mohammed A. Hameed
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2019 Volume: 15 Issue: 4 Pages: 33-36
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, silicon nitride nanostructures were synthesized by dc reactive magnetron sputtering technique. The effect of deposition time on the structural characteristics, especially structural purity and nanoparticle size, was determined. Long deposition time allows more silicon atoms sputtered from the target to bond to nitrogen atoms and form silicon nitride molecules. Therefore, the structure of the final product is highly dominated by silicon nitride as confirmed by the x-ray diffraction pattern. On the other hand, nanoparticles with larger size were grown at long deposition time. As the deposition time was increased from 3 to 4 hours, the nanoparticle size was increased from 26.10 to 101.20 nm. The structural characteristics of silicon nitride nanoparticles can be sufficiently controlled by the preparation conditions to serve certain applications based on nanoparticle size.


Article
Structural Characteristics of Nickel Ferrite Nanoparticles Synthesized by New Arrangement of Concentric Targets in DC Reactive Magnetron Sputtering

Authors: Firas J. Kadhim --- Ruaa A. Mohammed
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 4 Pages: 9-12
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Nickel ferrite (NiFe2O4) nanostructures were synthesized by co-sputtering of Ni and Fe targets in presence of oxygen. A dc plasma sputtering system employing closed-field unbalanced magnetron at the anode was used for the preparation of these films. The structural characteristics of the prepared films were determined and the results showed that these films are polycrystalline, highly pure, with average particle size of 20-25nm and average surface roughness of 0.465nm. These nickel ferrite nanostructures were prepared at low production cost, high reliability and reasonable structural purity.

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