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Article
Linear Optical Properties of Bromocresol Green Dye Doped Poly Methyl Methacrylate Thin Films
الخواص البصرية الخطية لاغشية بولي مثيل ميثاكرلايت المطعمة بصبغة بروموكريسول الخضراء

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Abstract

In this study, we investigated the effect of Bromocresol green dye (BCG) of the PMMA thin films optical properties. Films of Poly Methyl Methacrylate doped by 10% BCG doping ratio to prepared two concentrations 2x10-4 and 6x10-4 M of PMMA-BCG dye were deposited on glass substrate using free casting method at room temperature. The optical properties of the films were determined using UV-Visible absorbance and transmittance spectra at the 300 - 900 nm wavelength range. The linear absorption coefficient and the extinction coefficient were calculated. The results showed that the optical properties were increasing by increasing the dye concentration, while the optical energy gap was decreasing with the doping. Also from the linear optical properties result the PMMA-BGC thin films are a promised materials for nonlinear optics applications.

درسنا تاثير التطعيم بصبغة بروموكريسول الخضراء على الخواص البصرية الخطية لاغشية البوليمر (بولي مثيل ميثا اكريلايت). تم تحضير هذه الاغشية المكونة من بولي مثيل ميثا اكريلايت المطعم بنسبة 10% صبغة بروموكريسول الخضراء لتحضير تركيزين (2×10-4, 6×10-4 مولاري) من غشاء بولي مثيل ميثاكرلايت – بروموكريسول الخضراء بواسطة طريقة الصب الحر على الواح زجاجية بدرجة حرارة الغرفة). تم قياس الخواص البصرية الخطية من خلال قياس اطياف الامتصاص والنفاذية ضمن المدى الطيفي 300- 900 نانو متر, اذ تم حساب المعاملات البصرية مثل معامل الامتصاص، معامل الانكسار، معامل الخمود، وفجوة الطاقة. اظهرت النتائج بأن المعاملات البصرية الخطية تزداد بأزدياد نسبة التطعيم للصبغة فيما لاحظنا نقصان في فجوة الطاقة البصرية مع ازدياد نسبة التطعيم. كما اظهرت النتائج ايضا ان هذا المادة ممكن ان تكون مادة واعدة لتطبيقات البصريات اللاخطية


Article
Analysis of Atomic and Electronic Structures of NiO/Au Interfaces by High-Resolution MEIS and Photoelectron Spectroscopy

Author: Jamal H. Jasim, Yaser H. Kasim, Fadhil A. Hasan
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2018 Volume: 14 Issue: 3 Pages: 13-20
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

The atomic and electronic structures of NiO(001)/Au(001) interfaces were analyzed by high-resolution medium energy ion scattering (MEIS) and photoelectron spectroscopy using synchrotron-radiation-light. The MEIS analysis clearly showed that O atoms were located above Au atoms at the interface and the inter-planar distance of NiO(001)/Au(001) was derived to be 2.30±0.05Å, which were consistent with the calculations based on the density functional theory (DFT). We measured the valence band spectra and found metallic features for the NiO thickness up to 3 monolayer (ML). Relevant to the metallic features, electron energy loss analysis revealed that the band gap for NiO(001)/Au(001) reduced with decreasing the NiO thickness from 10 down to 5 ML. We also observed Au 4f lines consisting of surface, bulk, and interface components and found a significant electronic charge transfer from Au(001) to NiO(001). The present DFT calculations demonstrated the presence of an image charge beneath Ni atoms at the interface just like alkali-halide/metal interface, which may be a key issue to explain the core level shift and band structure.


Article
Optical and Structural Properties of (In2O3:ZnO:Au) Nanocomposite Thin Films Prepared by Spray Pyrolysis Method

Authors: Abdulhadi Kadhim --- Farah T.M. Noori --- Nawres D. Hamza
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 1 Part (B) Scientific Pages: 53-58
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Indium Oxide (In2O3) and Zinc Oxide (ZnO) nanoparticles weremixed carefully with gold nanoparticles, which were synthesis, by turkevichmethod. By using the method of spray pyrolysis different concentrations(5:5:0 ml, 5:4:1 ml, 5:3:2 ml, 5:2:3 ml, 5:1:4 ml and 5:0:5 ml) from thesechemical compounds were used to preformed nanocomposite thin films ofthickness of (250-300) nm. The structural properties were studied for allnanocomposite thin film samples with different concentrations. The existenceof Miller indices conforms to (211), (222), (400), (333), (440) and (622) majorlattice planes of the cubic spinel phase of In2O3 at 2θ =20.17, 33, 44.66, 50.95,59.02, 72.48 and 73.12. While secondary lattice planes of (100) and (002) ofZnO at 2θ = 31.5582 and 34.1617, also lattice planes of (111) and (200) ofAu were found at 2θ = 38.5799 and 45.6016. The work also extended to studythe optical properties, which included the transmission spectrum, absorptionspectrum, absorption coefficient, attenuation coefficient and estimation ofoptical energy gap for all samples. The results of optical properties wereclearly demonstrated that the increasing of gold concentration is decreasingthe transmission, and decreasing the optical band gap from 3.10 to 3.05 eV,but increasing the absorption coefficient and attenuation coefficient. FinallyThe real and imaginary part of dielectric constant of (In2O3:ZnO:Au)nanocomposite thin film with different concentrations decrease withincreasing of frequency, and increases with gold nanoparticles increasing.


Article
Nanostructured CdSnSe Thin Films Prepared by DC Plasma Sputtering of Thermally Casted Targets

Author: Oday A. Hammadi
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2018 Volume: 14 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, nanostructured cadmium tin selenide (CdSnSe) thin films were deposited on glass substrates by dc plasma sputtering technique. The sputtered target was prepared by the thermal casting of Cd, Sn and Se samples at 350°C. The structural characterizations showed that the prepared targets were polycrystalline while the deposited CdSnSe films exhibited amorphous structure due to the growth of nanostructures on the substrates, which was also confirmed by the scanning electron microscopy. These films showed high absorption in the ultraviolet and visible regions while low absorption was observed in the near-infrared region (>800nm). They have two allowed types of energy band gaps; indirect at 1.233eV and direct at 1.655eV. The dispersion relationship showed that these films have approximately constant refractive index in the visible region, which is attributed to the optical homogeneity of the prepared films.


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
The Influence of RF power, pressure and substrate temperature on optical properties of RF Sputtered vanadium pentoxide thin films
تاثير الطاقة والضغط ودرجة حرارة الركيزة على الخصائص البصرية للاغشية الرقيقة لخامس اوكسيد الفاناديوم باستخدام الترذيذ بالترددات الراديوية

Authors: Ibrahim K. salman إبراهيم خلف سلمان --- N.K. Hassan نديم خالد حسن --- Mohammed K. Khalaf محمد خماس خلف
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2018 Volume: 16 Issue: 39 Pages: 42-47
Publisher: Baghdad University جامعة بغداد

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Abstract

The V2O5 films were deposited on glass substrates which produce using "radio frequency (RF)"power supply and Argon gas technique. The optical properties were investigated by, UV spectroscopy at "radio frequency" (RF) power ranging from 75 - 150 Watt and gas pressure, (0.03, 0.05 and 0.007 Torr), and substrate temperature (359, 373,473 and 573) K. The UV-Visible analysis shows that the average transmittance of all films in the range 40-65 %. When the thickness has been increased the transhumance was decreased from (65-40) %. The values of energy band gap were lowered from (3.02-2.9 eV) with the increase of thickness the films in relation to an increase in power, The energy gap decreased (2.8 - 2.7) eV with an increase in the pressure and substrate temperature respectively.

تم ترسيب أغشية رقيقة من خامس اكسيد الفاناديوم على ركائز زجاجية التي تنتج باستخدام طاقة التردد الراديوي وتقنية غاز الأرجون، وتم بحث الخواص البصرية بواسطة دراسة مطيافية مرئية فوق بنفسجية عند قدرة التردد الراديوي من 75 - 150 واط وضغط الغاز 0.03 تور، .050 تور و 0.007 تور، ودرجة حرارة الركيزة (359، 373، 473 و 573) كلفن. أظهر التحليل الطيفي المرئي و للأشعة فوق البنفسجية أن متوسط نفاذ جميع الأغشية يكمن في نطاق 40-65 ٪ و عندما زاد السمك انخفضت نسبة الانتقال مـــن (65 -40) %. و انخفضت فجوة النطاق الضوئي للغشاء من 3.02 إلى 2.9 الكترون فولت, مع زيادة سماكة الأغشية مقارنة بالزيادة في القدرة، من ناحية أخرى انخفضت فجوة النطاق من 2.8 إلى 2.7 الكترون فولت, مع زيادة الضغط ودرجة حرارة الركيزة على التوالي.


Article
Studying the Effect of Annealing Temperature on some Physical Properties of In2O3 Thin Films

Authors: Duaa A. Mohammed --- Muslim F. Jawad
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 2 Part (B) Engineering Pages: 124-127
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this study, In2O3 thin films were deposited on quartz substrates bypulsed laser deposition technique at room temperature and followed bythermally annealing at 300℃, 400℃ and 500℃ for 1 hour. The optical bandgap was found to increase with the annealing temperature from 3.5 to 3.85 eVand the transmittance was observed above 90%. XRD results show that the filmsare polycrystalline in nature and crystallizes with preferred orientation (222).SEM images show that the films are high homogenous and they containeduniformly distributed small grains.


Article
The Growth Characteristics of RF-Magnetron Sputtered Nanocrystalline TiO2 Thin Films

Authors: Azhar K. Sadkhan --- Suaad A. Mohammed --- Mohammed K. Khalaf
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 2 Part (B) Engineering Pages: 128-130
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper, RF Magnetron sputtered TiO2 thin films deposited onglass slices at various powers (75,100,125 and 150) Watt for (1.5) hour anddifferent thickness (62.5-88-118 and 132.6) nm, the TiO2 thin films annealed with400°C for 2 hour and the morphology and structure of these films are describedby X-ray diffraction XRD and atomic force microscopy AFM to show the phasestructure. X-ray diffraction investigation uncovered that the crystalline size of theTiO2 thin films displays an expanding pattern with increasing the sputteringpower. The preferred orientation of (101) was watched for the films depositedwith sputtering power of (75,100,125 and 150) Watt


Article
D.C conductivity of In2O3: SnO2 thin films and manufacturing of gas sensor
التوصيلية الكهربائية المستمرة وتصنيع متحسس غازي من اغشية اوكسد الانديوم المطعم باوكسيد القصدير

Authors: Bushra A. Hasan بشرى عباس حسن --- Rusul M. Abdallah رسل محمد عبدالله
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2018 Volume: 16 Issue: 37 Pages: 32-45
Publisher: Baghdad University جامعة بغداد

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Abstract

Compounds were prepared from In2O3 doped SnO2 with different doping ratio by mixing and sintering at 1000oC. Pulsed Laser Deposition PLD was used to deposit thin films of different doping ratio In2O3: SnO2 (0, 1, 3, 5, 7 and 9 % wt.) on glass and p-type wafer Si(111) substrates at ambient temperature under vacuum of 10-3 bar thickness of ~100nm. X-ray diffraction and atomic force microscopy were used to examine the structural type, grain size and morphology of the prepared thin films. The results show the structures of thin films was also polycrystalline, and the predominate peaks are identical with standard cards ITO. On the other side the prepared thin films declared a reduction of degree of crystallinity with the increase of doping ratio. Atomic Force Microscopy (AFM) measurements show the average grain size exhibit to change in non-systematic manner with the increase of doping ratio with tin oxide. The average grain size increases at doping ratios 1, 5 and 7 % from 52.48 to 79.12, 87.57, and 105.59 nm respectively and decreases at residual doping ratio. The average surface roughness increases from 0.458 to 26.8 nm with the increase of doping ratio. The gas sensing measurements of In2O3:SnO2 thin films prepared on p-Si to NO2 gas showed good sensitivity and Maximum sensitivity (50) obtained for In2O3:SnO2 prepared on p-Si at operating temperature 573 K and doping ratio 7 % and 9 %. Maximum speed of response time (8 sec) at operating temperature 573 K and doping ratio 1 %.

حضرت مركبات من اوكسد الانديوم المطعم باوكسيد القصدير وبنسب تطعيم مختلفة وذلك بمزج المركبين وتلبيدها عند درجة 1000 oC. تم استخدام طريقة التبخير بالليزر النبضي لتحضير اغشية رقيقة من المركب In2O3:SnO2 وبنسب تطعيم 9 % wt.) (0, 1, 3, 5, 7, على قواعد من الزجاج ورقائق السليكون مفرد االبلورة. وعند درجة حرارة المحيط وعند ضغط فراغ 10-3 تور وبسمك 150نانومينر. تم استخدام حيود الاشعة السينية ومطياف القوى الذرية لفحص تركيب, الحجم الحبيبي وطبوغرافية الاغشية المحضرة. اظهرت النتائج ان الاغشية المحضرة كانت متعددة البلورة وان المستوي المفضل للنمو متطابق مع بطاقات اوكسيد الانديوم- القصدير ومن جهة اخرى اظهرت الاغشية المحضرة هبوطا في درجة التبلور مع زيادة نسبة التطعيم. قياسات مطياف القوى الذري اظهرت ان حجم الحبيبة تغير بشكل غير منتظم مع نسبة التطعيم. حيث ازداد حجم الحبيبة عند نسب التطعيم 1, 5, 7 % من 52 الى 79, 87و 105 نانوميتر على التوالي وهبط عند نسب التطعيم الباقية. خشونة السطح ازدادت من0.458 الى26.8 نانوميترمع زيادة نسبة التطعيم. قياسات التحسسية لاغشية In2O3:SnO2 المحضرة على قواعد من السليكون نوع p لغاز NO2 كانت جيدة و اقصى قيمة للتحسسية كانت (50) لاغشية In2O3:SnO2 المحضرة عند درجة تشغيل 573 K ونسب تطعيم 7 % ,.9% اقصى زمن استجابة كان(8 sec) عند درجة تشغيل 573 K و نسبة تطعيم 1%.


Article
Preparation and Characterization of Polymer Blend (PVA/PEO) Filled with Methyl Orange Thin Films

Authors: Ahmed Namah Mohamed --- Jafer Fahdel Odah --- Haider Tawfiq Naeem
Journal: Diyala Journal For Pure Science مجلة ديالى للعلوم الصرفة ISSN: 83732222 25189255 Year: 2018 Volume: 14 Issue: 02 Pages: 221-234
Publisher: Diyala University جامعة ديالى

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Abstract

Polymers blend PVA/PEO filled with different weight percent ratios of methyl orange was used to prepare films via casting method. Structural properties of the final thin films were carried out using XRD technique, FTIR and optical microscope. While the absorption spectra of these films were measured using UV-VIS double beam spectrometer in the wavelength range of (190-1100) nm. The optical coefficients such absorption coefficient and extinction coefficient were calculated from the optical absorption. Direct and indirect allowed electronic energy transitions were studied under the influence of MO weight percent variation (0, 10, 20, 30, 40 and 50) wt %.

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