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Article
The Effects of Sputtering Time on Cds Thin Film Solar Cell Deposited by DC Plasma Sputtering Method

Authors: Azhar K. Sadkhan --- Mohammed K. Khalaf
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 2 Part (C) Pages: 123-127
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

CdS thin films of different thickness have been prepared by dcsputtering technique on glass slides for a window layer of solar cells. The CdStarget were sputtered in different sputtering times (1,1.5,2.5,3) hrs, workingpressure (2×10-2) mbar and discharge voltage(2) kV.The structure of thenanoparticles films was investigated of CdS thin films by X-ray diffraction(XRD).The XRD patterns showed that the films were hexagonal (wurtzite)structure having strong preferential orientation along the (002) plane withparticle size in the range of (41.04-41.46-41.88-42.53) nm, the peak at (002)preferred orientations of the films are shifted a little from left to right side andfilms converted to crystalline form. The morphology of the nanoparticles filmswas studied by atomic force microscopy (AFM) which indicates that theaverage grain size of CdS thin film is in the range of (41.3-44.2-51.6-50.08) nm.The roughness of films surface increases with increasing the sputtering time,which can be useful for the solar cell.


Article
Effect of Adding Nitrogen to the Gas Mixture on Plasma Characteristics of a Closed-Field Unbalanced DC Magnetron Sputtering System

Authors: Firas J. Kadhim --- Mohammed K. Khalaf --- Oday A. Hammadi
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2014 Volume: 10 Issue: 1 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

In this work, the role of adding nitrogen gas to the discharge gas mixture containing argon was studied by introducing the electrical characteristics of plasma generated between two closed-field unbalanced magnetron electrodes. This role was also related to the presence and absence of magnetron at the electrodes in the fundamental design of such sputtering system. The role of nitrogen gas added to the gas mixture was reasonably observed by enhancing the electrical characteristics of the glow discharge plasma generated between the dual CFUBM electrodes. Adding nitrogen caused to increase the concentration of the charged particles produced by collisional ionization in discharge volume as the mean free path of primary discharge electrons was reduced. A relative reduction in electron temperature was observed as a result of adding nitrogen with increase in electron and ion densities while no observed difference was observed in the ion temperature due to their larger masses compared to those of electrons.


Article
Influence of Inter-Electrode Distance, Gas Mixing, Magnetic Field and Cathode Material on Breakdown Voltage of Lab-Made DC Magnetron Sputtering Device

Authors: Mohammed K. Khalaf --- Ibrahim R. Agool --- Shaimaa H. Abd Muslim
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2014 Volume: 10 Issue: 4 Pages: 21-25
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 paper, the effect of inter-electrode distance, gas mixing, magnetic field and cathode materials on breakdown voltage in DC glow discharge of argon and argon-oxygen plasma is presented. The results showed an increased breakdown voltage when inter-electrode distance and oxygen percentage in (Ar∕O2) gas mixture increased. At lower pressure, the breakdown voltage decreases by increasing the magnetic field, while at higher pressure, the breakdown voltage becomes less sensitive to the magnetic field. Moreover, the lower breakdown voltages are associated with smaller work function of the cathode material.


Article
Characterization of the Copper Oxide Thin Films Deposited by Dc Sputtering Technique
دراسة خصائص اغشية اوكسيد النحاس المحضرة بطريقة الترذيذ للتيار المستمر

Authors: Mohammed K. Khalaf --- Saba N. Said --- Ameen J. Abbas
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 4 Part (B) Scientific Pages: 770-776
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Nanocrystalline Copper Oxide films were deposited on glass substrates by plasma dc sputtering. The effected of discharge current on the structural and optical properties of sputtered films were studied .X-ray diffraction peak of Cu2O (111) and Cu4O3 (112) direction was observed at discharge current of (15-30) mA when annealed at 500 0C for 2 h. The optical energy gap for the prepared films is estimated to be in (2.05- 2.3) eV range. It was found that the effect of preparation conditions on thin films thickness strongly depends on the discharge current of argon plasma.

تم في هذا البحث تحضيرأغشية نانويه من مركبات اوكسيد النحاس رسبت على قواعد زجاجية باستخدام الترذيذ بالبلازما . تم مناقشة تاثير تيار التفريغ على الخصائص التركيبية والبصرية وباستخدام حيود الأشعة السينية والتي أوضحت وجود التركيب متعدد التبلور. ظهرت في الأغشية المحضرة بتيار تفريغ يتراوح بمدى 15-30) mA) والملدنة بدرجة حرارة 500 0C لمدة ساعتين وجود مستويات (112),(111) للاطوار(Cu2O,Cu4O3). كما وجد إن فجوة الطاقة البصرية للأغشية المحضرة تتراوح من 2.05-2.3) eV). كما وجد إن سمك الأغشية المحضرة يتأثر مع تيار التفريغ لبلازما الاركون.

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Article
Discharge Characteristics on the Synthesis of Carbon Nanostructures through Arc-plasma in Water
خصائص التفريغ عند تكوين التراكيب النانوية بتقنية قوس البلازما في الماء

Authors: Bahaa.T.Chaid --- Mohammed.K.Khalaf --- Hassan.Z.Ali
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 6 Part (B) Scientific Pages: 1120-1127
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Simple arc discharge technique was used for formation of carbon nonmaterials without using any type of gases. The used arc discharge technique between the pure graphite electrodes with different diameters for anode submerged in water at room temperature. Arc plasma is produced using D.C power supply with current (30-90amp), and voltage (5-25volt).The discharge characteristics of the arc plasma generation in water and, with Ni catalyst and in NaCl solution were examined with the change in working parameters of electrode diameters and related arc current. The nanostructures obtained of these experiments were examined by scanning electron microscope (SEM).

استخدام تقنيه بسيطه لتكوين مواد كاربونيه نانوية باستخدام التفريغ بالقوس. تقنية التفريغ القوس تمت باستخدام أقطاب كاربونيه (قطب الانود) ذات أقطار مختلفة مغمورة بالماء وبدرجة حرارة الغرفة.تم توليد البلازما باستخدام مجهز قدره بتيار(30-100) امبير و فولتيه (5-25) فولت .خصائص التفريغ درست في الماء وبوجود بلورة النيكل وكذلك في محلول كلوريد الصوديوم مع تغيير قطر الانود المرتبط بتغير تيار القوس. ان المواد النانوية المنتجة بهذه التجارب تم فحصها باستخدام مجهر الماسح الالكتروني .


Article
Photovoltaic Properties of CdS/Si Heterojunction Prepared by DC Plasma Sputtering Technique

Authors: Mohammed K. Khalaf --- Sabah Habeeb Sabeeh --- Azhar K. Sadkhan
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 2 Part (B) Scientific Pages: 311-316
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

CdS/Si heterojunction has been fabricated by dc plasma sputtering technique. Polycrystalline CdS films have been prepared by dc plasma sputtering technique on Si substrate. The current – voltage under illumination showed that the photocurrent increases with increasing incident illumination intensity for CdS/Si heterojunction. The CdS thin films have been sputtered under vacuum of (9×10-2 ,8×10-2, 6×10-2,5×10-2) mbar, theheterojunction has better photovoltaic properties. The open circuit voltage (Voc) and the short circuit current (Isc)were found to vary with working discharge pressure, and the efficiency is 6.72% at 50.3 mW/cm2.


Article
Current-Voltage Characteristics of DC Plasma Discharges Employed in Sputtering Techniques
خصائص تيار-جهد لتفريغ البلازما المستمر المستخدم في تقنيات الترذيذ

Authors: Mohammed K. Khalaf --- Oday A. Hammadi --- Firas J. Kadhim
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 3 Pages: 11-16
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, the current-voltage characteristics of dc plasma discharges were studied. The current-voltage characteristics of argon gas discharge at different inter-electrode distances and working pressure of 0.7mbar without magnetrons were introduced. Then the variation of discharge current with inter-electrode distance at certain discharge voltages without using magnetron was determined. The current-voltage characteristics of discharge plasma at inter-electrode distance of 4cm without magnetron, with only one magnetron and with dual magnetrons were also determined. The variation of discharge current with inter-electrode distance at certain discharge voltage (400V) for the cases without magnetron, using one magnetron and dual magnetrons were studied. Finally, the discharge current-voltage characteristics for different argon/nitrogen mixtures at total gas pressure of 0.7mbar and inter-electrode distance of 4cm were presented.


Article
Structural Properties of Nickel Oxide Nanostructures Prepared by Closed-Field Unbalanced Dual Magnetron Sputtering Technique

Authors: Firas J. Kadhim --- Oday A. Hammadi --- Mohammed K. Khalaf
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2017 Volume: 13 Issue: 2 Pages: 3-10
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, nickel oxide nanostructures were prepared by a closed-field unbalanced dual magnetron plasma sputtering technique. The structural characterizations performed on the prepared samples showed that they were polycrystalline and the optimization of preparation conditions, only two crystal planes; (111) and (012), were observed in the final product. The surface roughness of the nanostructures can be varied by controlling the inter-electrode distance. Minimum particle size of 25nm was determined for the samples prepared at inter-electrode distance of 6cm.


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
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

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