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Article
The Effect Of Thermal Oxidation Time On The Structure And Influence On Optical Properties For Porous Silicon Prepared By Photo Electrochemical Etching
تاثير زمن الاكسدة الحرارية على الخصائص التركيبية وتاثيرها على الخصائص البصرية للسيلكيون المسامي المحضر بطريقة الكهروكيميائية

Authors: Narges Z.Abd alzahra --- Alwan M.Alwan
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2009 Volume: 27 Issue: 4 Pages: 727-735
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The morphological properties of the freshly and oxidized porous silicon atoxidation time (60, 90) sec were studied. A blue emission from PSi can be seen witheyes after thermal oxidation because the increasing of energy gab due to decreasedsilicon column (nano particles).Pore size and shape of n-type wafers are estimate andcorrelated with optical properties before and after rapid thermal oxidation (RTO).

في هذا البحث تم دراسة تأثير الأكسدة الحرارية السريعة على السليكون المسامي المحضر بطريقة القشط الكهروضوئيكيميائي على طبوغرافية السليكون المسامي . وقد تم من خلال صور الماسح الالكتروني حساب قطر وتوزيع المسامات وحسابحجم العمود الفاصل بين المسامات قبل وبعد عملية الأكسدة الحرارية كما تم قياس الخصائص البصرية والكهربائية قبل وبعدالمعالجة الحرارية


Article
Investigation of optical properties of cadmium sulfide (CdS) thin films by chemical bath deposition
دراسة الخصائص البصرية لأغشية رقيقة لمركب كبريتيد الكادميوم بأستخدام طريقة الترسيب بالحمام الكيميائي

Authors: Wessal Aead Taha وصال اياد طه --- Ali M. Mousa علي مطشر موسى --- Selma M. H. Al-Jawad سلمى محمد حسين
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2009 Volume: 6 Issue: 1 Pages: 150-162
Publisher: Baghdad University جامعة بغداد

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Abstract

Thin films of CdS were deposited on glass substrates using a chemical bath deposition technique from aqueous solutions of Cadmium sulfate (CdS) and thiouria. The films grown from the bath are uniform and adherent, have a high transmittance in the visible region. The CdS films properties studied include optical transmission, optical constant, dielectric constant, optical conductivity, and band gaps. The films in this study produced fairly high transmission (> 86% between 500 and 900). Band gaps of (2.4 eV) for direct transition were obtained. Such films could be used as photocells and other photoconductive devices, thin film transistors and diodes, piezoelectric ultrasonic transducers and amplifiers, piezoelectric acoustic resonators and electron beam-pumped lasers.

في هذا البحث تم ترسيب الاغشية الرقيقة لكبريتيد الكادميوم على قواعد من الزجاج بأستعمال تقنية الترسيب بالحمام الكيميائي من محلول مائي لكبريتيد الكادميوم (CdS) والثايوريا. الاغشية المحضرة تمتاز بكونها منتظمة ،ذات التصاقية وتمتلك نفاذية عالية في المنطقة المرئية . الدراسة التي تمت لأغشية كبريتيد الكادميوم تتضمن النفاذية البصرية، الثابت البصري ،ثابت العزل الكهربائي ،التوصيلية الضوئية ،فجوة الطاقة . الاغشية التي تمت دراستها في هذا البحث لها نفاذية عالية تصل الى اكبر من 86% لأطوال موجية تتراوح بين (500نانومتر الى 900نانومتر) وفجوة الطاقة 2.4 الكترون فولت.


Article
The effect of Cd substitution in PbS thin film on the optical properties
تأثير استبدال الكادميوم Cd على الخواص البصرية للغشاء الرقيق PbS

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Abstract

Abstract:Thin films of Cd¬x¬Pb¬1-x S were prepared by chemical spray pyrolysis with
( x=0.6 , 0.7 , 0.8 , 0.9 , 1 ) .The optical properties of prepared thin films were studied by UV-VIS spectrophotomer . From the measurement of absorption and transmission , the optical parameters and the optical energy gap (Eg) were calculated .The optical energy gap (Eg) was increased with increasing the value of Cd from 1.2 eV when x=0.6 to 2.4 eV when x=1 . The maximum value of refractive index (n) is equal to 2.5 and the maximum value of extinction coefficient is varied between 0.2 to 0.45 depending on the value of x . The film with x=0.7 was doped by Ag in the ratio 1% ,3% and 5% . The film after dopping have a direct energy gap also and the value of Eg were increased with increasing (Ag) ratio , these values increased from 1.2 eV for absent Ag to 1.74 eV for 5% Ag .

وقد درست الخواص . x = بطريقة الرش الكيميائي الحراري لقيم 0.6,0.7,0.8,0.9,1 CdxPb1-xS تم تحضيراغشية رقيقة منمن قياسات طيف الامتصاصية والنفاذية تم حساب الثوابت البصرية . UV-VIS البصرية للاغشية المحضرة باستخدام مطيافx= 1.2 عندما 0.6 eV من Cd حيث كانت قيمة فجوة الطاقة البصرية تزداد بزيادة نسبة الكادميوم . Eg وفجوة الطاقة البصريةتتغير بين k تساوي 2.5 ، وكذلك فان قيمة معامل الخمود (n) وقد وجد ان اعلى قيمة لمعامل الانكسار . x= الى 2.44 عندما 11,3,5 .وقد وجد ان الغشاء wt% بعنصر الفضة وبنسب x = تم تطعيم الغشاء عند قيمة 0.7 . x 0.2 الى 0.45 معتمدة على قيمة1.2 في حالة غياب الفضة الى 1.74 eV بعد تطعيمه يمتلك فجوة طاقة مباشرة تزداد بزيادة نسبة الفضة هذا القيمة تزداد من. % عندما تكون نسبة الفضة 5 eV


Article
STUDYING THE CONDUCTIVITY OF POLY(VINYL CHLORIDE) USING 2-(SUB.)-5-[3-(5-NITRO-FUR-2-YL)-PROPEN-2-YLDIENE]AMINO –1,3,4THIDIAZOLES AS ADDITIVES BY MEASURING FORBIDDEN ENERGY GAP

Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2009 Volume: 12 Issue: 2 Pages: 101-106
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Optical properties such as direct and indirect optical energy gap, and optical absorption edge were investigated in pure and doped Poly (vinyl chloride) films from their optical absorption spectra in the 200–600 nm wavelength regions. The direct optical energy gap for pure Poly(Vinyl Chloride) lies at 5.7 eV while it ranges from 4.65 to 5.22 eV for different composition films. Similar behavior was observed for the indirect optical energy gap and absorption edge. It was found that the energy gaps and band edge values shifted to higher energies on doping with 2-(sub.)-5-[3-(5-nitro-fur-2-yl)-propen-2-yldiene] amino –1,3,4-thidiazoles. Measurements of the conductivity were made to investigate the order of conductivity and charge transport in this polymer electrolyte

الخصائص البصرية وفجوة الطاقة المحظورة للانتقالات المباشرة وغير المباشرة, وحافة الامتصاص البصري, تمت فحصها لشرائح لمركب (PVC) النقي والمشوب من خلال طيف الامتصاص البصري للأطوال الموجية من 200 – 600 نانومتر. فجوة الطاقة للانتقال المباشر لمركب (PVC) النقي تقع عند 5.7 إلكترون فولط في حين تمتد قيمها من 4.65 – 5.22 ولمختلف التراكيز. نفس التصرف يحدث أيضا لفجوة الطاقة المحظورة للانتقال الغير المباشر وحافة الامتصاص. وجد أن قيم فجوة الطاقة وحافات الحزم تحيد إلى مستويات طاقة عليا عند التشويب بـــ (2-(sub.)-5-[3-(5-nitro-fur-2-yl)-propen-2-yldiene] amino –1,3,4-thidiazoles). قياسات التوصيلية وانتقالات الشحنة تم دراستها للبوليمر.


Article
Temperature-Dependent Birefringence Properties of Be3Al2Si6O18 Crystal

Authors: M.A. Albarazanchy --- I.K. Hama --- G.M. Najeeb
Journal: Iraqi Journal of Applied Physics Letters الرسائل العراقية في الفيزياء التطبيقية ISSN: 1999656X Year: 2009 Volume: 2 Issue: 1 Pages: 12-14
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

The temperature dependence of the refractive indices for ordinary and extraordinary rays of mercury spectrum three lines and laser line independently one from the other were measured in temperature interval 20-600°C. It was obtained that the refractive indices increase along with the temperature growth and this dependence has quasilinear character. Emerald has quite low birefringence values that increases slightly along with the temperature growth and decreases with wavelength growth. The thermooptical coefficients for every wavelength were calculated. They have greater values for the extraordinary beams than for the ordinary ones. The dispersion curve for refractive indices was obtained.


Article
Optical Properties of Thermally-Annealed Tin-Doped Indium Oxide Thin Films

Author: A.I. Hasan
Journal: Iraqi Journal of Applied Physics Letters الرسائل العراقية في الفيزياء التطبيقية ISSN: 1999656X Year: 2009 Volume: 2 Issue: 2 Pages: 15-18
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, results of thermal annealing of tin-doped indium oxide thin films were presented. The effect of thermal annealing of the optical characteristics of such films was introduced. These characteristics include transmission, absorption coefficient, absorption depth, type of band gap and the dominant absorption processes. Thermal annealing may improve the diffusion of Sn dopants in the In2O3 structure and hence affect the optical properties of the resulted structure. The Sn-doped In2O3 thin films are widely used in the optoelectronics and integrated optics architecture.


Article
Influence of Post- Annealing on The Properties of Cuxs: Al, Fe Films Deposited By C B D
تأثيرالمعالجة الحرارية على خصائص أغشية كبرتيد النحاس المشوبة بالحديد والالمنيوم والمرسبة بطريقة الترسيب بالحمام الكيمياوي

Authors: Ali M . Mousa --- Abbas F. Sabbar
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2009 Volume: 27 Issue: 14 Pages: 2632-2641
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Thin films of copper sulfide (CuxS) were deposited at room temperature on glass substrates from solution containing copper (II) chloride, triethanolamine, and thiourea at appropriate pH (10-11). Two types of doping salts were used (AlCl3 & FeCl3) in four different weights (1, 1.5, 2, and 2.5) mg. The effect of introducing impurities and post-annealing was studied .The as-deposited films were found tobe amorphous, while the post annealed were polycrystalline. The changes in optical and electrical properties of doped films were also studied. The electrical conductivity was found to be highly dependent on annealing conditions, the resistivity of doped films was between (0.022-8.75) Ω cm. Optical band gaps of doped films determined from absorption spectra were found to have values within the range of (2.17-2.33) eV.

في هذا البحث رسبت أغشية رقيقة من مادة كبرتيد النحاس على قواعد زجاجية بدرجة حرارة الغرفة بأستخدام كلوريد النحاس ، تراي ايثانول امين و الثايوريا وبدالة حامضية ملأئمة FeCl 11-10 ). أستخدام نوعين من املاح الاشائبة هما كلوريد الحديد وكلوريد الالمنيوم ( 3 ) بأربعة أوزان مختلفة هي ( 1،1.5،2 و 2) ملغم.درس تأثير كل من أضافة الشوائب (AlCl3 & والمعالجة الحرارية. من خلال دراسة حيود الاشعة السينية تبين ان الاغشية المرسبة من غيرمعالجة حرارية تكون عشوائية بينما تلك المعالجة حراريا كانت متعددة البلورات. درس التغير في الخصائص البصرية و الكهربا ئية للأغشية المشابة . ظهر قياس التوصيلية الكهربا ئية انها تعتمد كثيرا على شروط المعالجة الحرارية. المقاومية الكهربلئية للاغشية المشابة كانت بين حددت فجو ة الطاقة البصرية للاغشية المشوبة من طيف . Ωcm (8.75- 0.022). eV (2.33- الامتصاصية وتتراوحت ( 2.17


Article
Optical and Structure Properties of MgxZn1-xO Thin Films by Pulsed Laser Deposition
دراسة الخصائصالبصریة و التركیبیة لاغشیة MgxZn1-xO بالترسیب بالليزر

Authors: Gehan E. Simon --- Adawiya J. Haidar
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2009 Volume: 27 Issue: 14 Pages: 2653-2665
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this study, the optical and structure properties of MgxZn1-xO thin films is reported. The MgxZn1-xO thin films were prepared on Glass substrates by Q-switch second harmonic Nd:YAG laser deposition technigue with wavelength of 532nm from a ZnO target mixed with Mg of (0-0.3) wt% , and the films deposited at temperature (250°C).The optical properties were characterized by transmittance and absorption spectroscopy measurements. For all the films the average transmission in the U.V (200-900) nm wavelength region was over 85% and the absorption edge shifted to a shorter wavelength as the magnesium concentration increased. The optical energy gap of MgxZn1-xO thin films, measured from transmittance spectra could be controlled between (3.3eV and 4.2eV) by adjusting magnesium concentration. X-ray diffraction was used to investigate the structure of the film. The refractive index of hexagonal MgxZn1-xO thin films decreases with the Mg concentration increase, such as at the wavelength of (500nm) the refractive index decreases from 1.93 to 1.85 as x increase from 0.15 to 0.3. The extinction coefficient and the complex dielectric constant were also investigate.


Article
Optical Properties of Annealed Cadmium Sulfide Thin Films Prepared by Chemical Bath Deposition

Authors: W.A. Taha --- Z.S. Ahmed --- S.M.H. Aljawad
Journal: Iraqi Journal of Applied Physics Letters الرسائل العراقية في الفيزياء التطبيقية ISSN: 1999656X Year: 2009 Volume: 2 Issue: 2 Pages: 19-22
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

CdS thin films were prepared by the chemical bath deposition technique. Annealing in air at different temperatures (300, 350, 400, 450, and 500)°C at constant time of 30min, also for different times (15, 30, 45, 60, and 90) min at constant temperature (300°C) is achieved. The CdS films showed, on average, 20% reflectance. The transmittance ranged between 80–92% for the films annealed at 60 and 45 min. On average, the refractive index of the CdS is 1.2 and the band gap is 2.4eV, the wide band gap semiconductor has a wide range of applications in areas including photocells and other photoconductive devices.


Article
Electrical and optical Properties of Poly(Crystal Violet Terephthalate)(PCVT)
Electrical and optical Properties of Poly(Crystal Violet Terephthalate)(PCVT)

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Abstract

An analysis was carried out to examine the conduction mechanism in poly crystal violet terephrthalate (PCVT) synthesized by condensation polymerization .Electrical measurement including (current-voltage) characteristics .The effect of temperature on conductivity with range(300-368)K ,also investigated the activation energy (Ea) was estimated from conductivity as a function of reciprocal temperature about 0.47eV.The deviation from Ohm's law has been analyzed in term of hopping available range conduction theories .Hopping conducting mechanism was concluded to be the most probable one interpreting the behavior of charge transport that was supplied by injector electrodes .Optical properties of polymer was also investigated by using thin film of polymer on a glass substrates .The type of transition and energy gap determined depending on data of absorption spectrum of this sample . Indirect allowed band gap can be calculated equal to about 1.56eV and phonon energy assistance in transition about 0.06eV. The value of energy gap indicated that polymer have semiconductive properties.

An analysis was carried out to examine the conduction mechanism in poly crystal violet terephrthalate (PCVT) synthesized by condensation polymerization .Electrical measurement including (current-voltage) characteristics .The effect of temperature on conductivity with range(300-368)K ,also investigated the activation energy (Ea) was estimated from conductivity as a function of reciprocal temperature about 0.47eV.The deviation from Ohm's law has been analyzed in term of hopping available range conduction theories .Hopping conducting mechanism was concluded to be the most probable one interpreting the behavior of charge transport that was supplied by injector electrodes .Optical properties of polymer was also investigated by using thin film of polymer on a glass substrates .The type of transition and energy gap determined depending on data of absorption spectrum of this sample . Indirect allowed band gap can be calculated equal to about 1.56eV and phonon energy assistance in transition about 0.06eV. The value of energy gap indicated that polymer have semiconductive properties.

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