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Article
An interesting experimental observation of O2 pressure effect on the surface roughness of ZnO thin films prepared by PLD technique

Author: A.J. Haider
Journal: Iraqi Journal of Applied Physics Letters الرسائل العراقية في الفيزياء التطبيقية ISSN: 1999656X Year: 2009 Volume: 2 Issue: 4 Pages: 3-4
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In the foregoing section, we have seen that a high quality semiconductor nanostructure can be fabricated using PLD. A relatively smooth surface and a high crystalline quality, which are appropriate for good optoelectronic devices and applications, were obtained at oxygen pressure of 5x10-2mbar. But at vacuum of 5x10-1 mbar, a very low crystalline and a rough surface were obtained. This surface characterization is important for applications in gas sensors and catalysis.


Article
Characterization of Quantum Well Diode Pumped Nd:YVO4 Using V-Shape Technique

Authors: A.J. Haider --- H.M. Hikmet
Journal: Iraqi Journal of Applied Physics Letters الرسائل العراقية في الفيزياء التطبيقية ISSN: 1999656X Year: 2008 Volume: 1 Issue: 1 Pages: 31-34
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

V-shape face pumping scheme was used, a comparison between the bulkand the QW laser was made when used as pumping sources in CW mode toa Nd:YVO4 disk crystal, the output power obtained for the bulk diode laserwas 29mW, and when using the QW diode laser the maximum outputpower obtained was 58mW. In pulsed mode when using internallytriggered bulk diode laser with prf=1.3kHz, the maximum emitted peakpower was found to be 40mW, with a resonator length L=13cm, while forexternal triggering with prf=3Hz, the maximum output peak power wasfound to be 145mW.


Article
Characterization of D.C. Sputtering System

Authors: A.S. Jabbar --- A.J. Haider --- A.M. Mousa
Journal: Iraqi Journal of Applied Physics Letters الرسائل العراقية في الفيزياء التطبيقية ISSN: 1999656X Year: 2008 Volume: 1 Issue: 1 Pages: 3-9
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

DC sputtering system was designed and fabricated and it used fordeposition cadmium films. The optimum conditions for deposition wasdetermined experimentally under different voltages, pressures, and inter -electrode distances. XRD spectra show a clear indication of (hcp) peakswhich belongs to pure cadmium metal.


Article
Characterization of Diode Laser-Pumped Nd:YVO4 Disk Laser

Authors: A.J. Haider --- K.I. Hajem --- M.K. Zaher
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2008 Volume: 4 Issue: 2 Pages: 31-34
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 describe experimental set up disk laser of Nd:YVO4 in active mirror configuration, face pumping and cooling by thermoelectric Cooler (TEC) type heat exchanger to over come the limitation of prior design. With (4x5x1mm) disk dimensions to investigate the relationship between the pumping power from a diode laser at (808nm) with the optical elements in the setup and with the output power. The results show that a (0-600)mW CW output power which indicate 56% efficiency at (1064nm) wavelength from Nd:YVO4 thin disk material when pumped with power between (0-1500) mW from a 808nm CW laser diode.


Article
Nanostructure Dopants TiO2 Films for Gas Sensing

Authors: A.J. Haider --- R.M.S. Alhaddad --- K.Z. Yahya
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2011 Volume: 7 Issue: 2 Pages: 27-31
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

Nanostructure TiO2 doped with noble metals such as (Ag, Pt, Pd, Ni) thin films were prepared by Pulsed Laser Deposition (PLD) on SiO2 and Si (111) substrates. The thin films structures were determined by X-ray Diffraction (XRD). XRD pattern shows an increase in the average size of the crystalline grains with the range (11.6-25) nm in the all film samples. The morphology properties were determined from Atomic Force Microscopy (AFM), which shows that the grain size of the nanoparticles observed at the surface depend on the type of metal dopant.TiO2 doped with 3 % Pt metal has the smallest grain size of (11.6nm ) and RMS roughness values of (28 nm). The produced thin films in this study have been exposed to 50 ppm CO gas concentration.TiO2 doped with noble metal has sensitivity of higher than pure TiO2 .TiO2 doped with Pt metal deposited on Si (111) has 23 % maximum sensitivity to CO gas with optimum operation temperature of 250°C.


Article
Titanium-Base Nanostructure Coatings for AISI M52 Tool Steel by Gas-Phase Mix Process

Authors: F.Q. Mohammed --- A. J. Haider --- A.D. Thamir
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 3 Part (A) Engineering Pages: 182-189
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Deposition of Multicomponent hard coatings (Ti-B-N-C) on the molybdenum high-speed tool steel (AISI M52) has been achieved by mixed vapor deposition technique to improve the mechanical properties of the surface. In this technique the coating materials that were supplied in the gas phase were produced from powders that vaporized by thermal energy (that is, PVD- Reactive Evaporation Process), while the reactor that used to deposit Ti-Base coatings is hot-wall chemical vapor deposition (HWCVD) system equipment. This combination results in technical and financial advantages. The structure of deposited Ti-Base hard film was characterized by XRD technique, Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray spectroscopy (EDX). Mechanical characterization of the hard films has been performed by using Vickers micro hardness tester and The Ball-on-disk wear tests. With different reactive gas flow rates that ranged from 500 to 3000Sccm(standard Cubic Centimeter per Minute), the film showed amorphous matrix with crystalline Nano fibers of Ti-B phase which led to achieve higher hardness of 2051HV and better wear resistance with relatively good COF values of 0.61 than the uncoated tools.


Article
Structural and morphological Properties for Zinc Oxide Doped with Silver Nanoparticles (ZnO:Ag) Deposited on a Polymer Substrate

Authors: N.A. Mohsen --- A. J. Haider --- N.N. Jandow
Journal: Journal of College of Education مجلة كلية التربية ISSN: 18120380 Year: 2017 Volume: 1 Issue: 3 Pages: 165-172
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Zinc Oxidedopedwith silver nanoparticles (AgNPS) were deposited onto flexible polypropelene carbonate (PPC) substrate with different concentrations of Ag of (2,4, and 6wt%),and deposited at constant substrates temperature of 250°C using the pulse laser deposition (PLD). The crystalline structures and morphologies of the prepared films were investigated by X-ray diffraction (XRD) patterns and atomic force microscopy (AFM) analysis, respectively. XRD spectra indicated that the films posses a hexagonal wurtzite crystal structure, with preferred orientation (002) . AFM analysis showed that the film surface became rougher when the ZnO concentration was increased.

رسبت جسيمات الفضة النانوية (AgNPs) المشوبة باوكسيد الخارصين (ZnO) على قواعد البولي بروبلين كاربونات(PPC) باختلاف نسب تراكيز مادة الفضة(2,4, and 6 wt%) وثبوت درجة حرارة القاعدة (250°C) باستعمال تقنية الترسيب بالليزر النبضي (PLD).درس التركيب البلوري والسطحيللاغشية المحضرة بوساطة حيود الاشعة السينية (XRD) ومجهر القوة الذرية (AFM) على التوالي. تشير نتائج حيود الاشعة السينية تشير الى ان الاغشية تمتلك تركيب بلوري سداسي متراص, مع اتجاه عمودي على محور C-axis بشدة عالية على المستوي (002). تحليل مجهر القوة الذرية تظهر ان سطح الغشاء اصبح اكثر خشونة بازدياد نسب التراكيز.

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