Yazar "Tombak, Ahmet" seçeneğine göre listele
Listeleniyor 1 - 20 / 26
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Al:ZnO ince filmlerin optik ve elektriksel özelliklerine gama ışınlarının etkileri(2015) Tombak, AhmetYarıiletken ZnO ince filmler elektriksel iletkenliği ve optik geçirgenliği yüksek malzeme olmalarından dolayı teknolojik açıdan pek çok yerde kullanılırlar. Bu sebepten malzemenin üretimi ve teknik açıdan kullanılabilirliğinin ölçümü önem kazanmaktadır. Bu çalışmada çeşitli altlıklar üzerine ZnO ince filminin oluşturulması ve değişik oranlarda Al katkılanmış ZnO ince filmlerin gama ışımasına maruz bırakılmasından sonra bazı parametrelerindeki değişim araştırıldı. Elde edilen yapının elektrik ve optik özellikleri incelendi. İnce filmlerin elektriksel iletkenlikleri Hall etkisi ölçüm sistemiyle oda sıcaklığında ölçüldü. Bazı optik parametreler UV-Vis spektrometrik yöntemle tayin edildi. Optik parametrelerle ilgili deneysel bulgular teorik hesaplamalarla karşılaştırıldı. Alınan bu ölçümler Al:ZnO yapıların gama ışımasına maruz bırakılmasının ardından tekrar yapıldı ve değişimler gözlendi. İnce filmlerin yapı analizi X ışınları kırınımı ile tayin edildi.Öğe Barrier height enhancement of metal/semiconductor contact by an enzyme biofilm interlayer(Taylor & Francis Ltd, 2013) Ocak, Yusuf Selim; Guven, Reyhan Gul; Tombak, Ahmet; Kilicoglu, Tahsin; Guven, Kemal; Dogru, MehmetA metal/interlayer/semiconductor (Al/enzyme/p-Si) MIS device was fabricated using -amylase enzyme as a thin biofilm interlayer. It was observed that the device showed an excellent rectifying behavior and the barrier height value of 0.78eV for Al/-amylase/p-Si was meaningfully larger than the one of 0.58eV for conventional Al/p-Si metal/semiconductor (MS) contact. Enhancement of the interfacial potential barrier of Al/p-Si MS diode was realized using enzyme interlayer by influencing the space charge region of Si semiconductor. The electrical properties of the structure were executed by the help of current-voltage and capacitance-voltage measurements. The photovoltaic properties of the structure were executed under a solar simulator with AM1.5 global filter between 40 and 100mW/cm(2) illumination conditions. It was also reported that the -amylase enzyme produced from Bacillus licheniformis had a 3.65eV band gap value obtained from optical method.Öğe Diester Molecules for Organic-Based Electrical and Photoelectrical Devices(Springer, 2017) Topal, Giray; Tombak, Ahmet; Yigitalp, Esref; Batibay, Derya; Kilicoglu, Tahsin; Ocak, Yusuf SelimDiester derivatives of terephthalic acid molecules were synthesized according to the literature. Au/Diester derivatives/n-Si organic-inorganic (OI) heterojunction-type devices were fabricated, and the current-voltage (I-V) characteristics of the devices have been investigated at room temperature. I-V characteristics demonstrated that all diodes had excellent rectification properties. Primary diode parameters such as series resistance and barrier height were extracted by using semi-log I-V plots and Norde methods, and were compared. It was seen that there was a substantial agreement between results obtained from two methods. Calculated barrier height values were about the same with 0.02-eV differences that were attributed to the series resistance. Ideality factors, which show how the diode closes to ideal diodes, were also extracted from semi-log I-V plots. Thus, the modification of the Au/n-Si diode potential barrier was accomplished using diester derivatives as an interlayer. The I-V measurements were repeated to characterize the devices at 100 mW/cm(2) illumination intensity with the help of a solar simulator with an AM1.5G filter.Öğe Effects of the r-GO doping on the structural, optical and electrical properties of CdO nanostructured films by ultrasonic spray pyrolysis(Springer, 2020) Imer, Arife Gencer; Gulcan, Mehmet; Celebi, Metin; Tombak, Ahmet; Ocak, Yusuf SelimUndoped and reduced graphene oxide (r-GO)-doped CdO films were prepared via the ultrasonic spray pyrolysis method with weight ratios of 1, 3 and 5% onto substrates. The successfully prepared films were characterized to understand the influence of r-GO dopant content on the morphological, structural, electrical and optical properties of the films by several diagnostic techniques. XRD measurement confirms that all the films were polycrystalline in the cubic phase of CdO with the preferred orientation (111). The optical band gap of the films decreases with the increase in doping amount. The r-GO@CdO nanostructured films were used as an interfacial layer to fabricate the heterojunction device and to investigate their electrical properties using current-voltage and capacitance-voltage measurements in the dark. The rectification properties of the studied devices increase with the r-GO dopant amount. The obtained results indicate that the r-GO content in the CdO films is responsible for the modification of physical properties of electronic device.Öğe Electrical and optical properties of Cu2ZnSnS4 grown by a thermal co-evaporation method and its diode application(Elsevier Sci Ltd, 2014) Tombak, Ahmet; Ocak, Yusuf Selim; Genisel, Mustafa Fatih; Kilicoglu, TahsinCu2ZnSnS4 (CZTS) is low cost and constitutes non-toxic materials abundant in the earth crust. Environment friendly solar cell absorber layers were fabricated by a thermal co-evaporation technique. Elemental composition of the film was stated by energy dispersive spectroscopy (EDS). Some optical and electrical properties such as absorption of light, absorption coefficient, optical band gap charge carrier density, sheet resistance and mobility were extracted. Optical band gap was found to be as 144 eV, besides, charge carrier density, resistivity and mobility were found as 2.14 x 10(19) cm(-3), 8.41 x 10(-4) Omega cm and 3.45 x 10(2) cm(2) V-1 s(-1), respectively. In this study Ag/CZTS/n-Si Schottky diode was fabricated and basic diode parameters including barrier height, ideality factor, and series resistance were concluded using current-voltage and capacitance-voltage measurements. Barrier height and ideality factor values were found from the measurements as 0.81 eV and 4.76, respectively, for Ag/CZTS/n-Si contact. (C) 2014 Elsevier Ltd. All rights reserved.Öğe Electrical and photoelectrical behaviour of heterojunctions based on novel oligomeric metal complexes(Wiley, 2015) Atlan, Metin; Ocak, Yusuf Selim; Paşa, Salih; Temel, Hamdi; Tombak, Ahmet; Kılıçoglu, Tahsin; Akkılıç, Kemal; Aydemir, Murat; 0000-0002-4238-5012; 0000-0002-4792-8821; 0000-0002-9997-1653; 0000-0002-7150-6522Naringenin-based Schiff base ligands with 4-aminobenzoic hydrazide were obtained as a unilateral form (L-1). The ligand was oligomerized by oxidative polycondensation reaction with NaOCl as an oxidant in an aqueous alkaline medium at 90 degrees C to form a functional oligomer (L-2), and its transition metal complexes such as those with Cu(II), Ni(II) and Zn(II) were prepared. The monomer and the oligomeric compounds were characterized using various techniques. Optical and electrical properties of the complexes were also investigated. All compounds showed indirect band gaps and they can be accepted as being in the semiconductor class. Organic-inorganic hybrid devices were obtained using n-Si inorganic semiconductor and the complexes. The characteristic parameters of the devices were determined using current-voltage (I-V) and capacitance-voltage measurements in the dark. Photoelectrical properties of the devices were investigated using I-V measurements under a solar simulator with an AM1.5 global filter. Copyright (C) 2015 John Wiley & Sons, Ltd.Öğe Electrical and photoelectrical characterization of a TTF/p-InP organic–inorganic heterojunction(Microelectronic Engineering, 2014) Kilicoglu, Tahsin; Tombak, Ahmet; Ocak, Yusuf Selim; Aydemir, MuratTetrathiafulvalene (TTF) with C6H4S4 molecular formula was used in the fabrication of organic inorganic (OI) heterojunction. The Al/TTF/p-InP/Au-Zn structure was fabricated by forming a thin TTF organic semiconductor on p-InP inorganic semiconductor and evaporating of Al metal on the film. The characteristic parameters of the device were determined by using current-voltage (I-V) and capacitance voltage (C-V) measurements. Interface state density distribution was calculated from the I-V characteristics. The I-V characteristics of the device were also examined at 100 mW/cm(2) illumination intensity by the help of a solar simulator with AM1.5 global filter. (C) 2014 Elsevier B.V. All rights reserved.Öğe Electrical and photoelectrical characterization of organic-inorganic heterostructures based on Ru-N-heterocyclic carbene complexes(Elsevier Gmbh, 2018) Yasar, Sedat; Cekirdek, Suzan; Binbay, Nil Ertekin; Tombak, Ahmet; Ocak, Yusuf Selim; Arslan, Nevin; Baysal, Akin1,3-Bis(2-morpholinethyl)benzimidazoliumtrichlorido(eta(6)-p-cymene)-ruthenate(11), 2, was synthesized and characterized by NMR spectroscopy and micro analysis. The organic -inorganic heterojunctions were fabricated by using n-type Si wafer and a series of Ru-N-heterocyclic carbene complexes, 3-5, bearing sterically hindered aryl groups were documented for the first time. The thin films of the complexes are deposited on n-Si substrates using spin coating. Current-voltage (I-V) measurements of the devices in dark and illuminated environments were analyzed to determine electrical parameters of devices. Furthermore, the photoelectrical properties of the structures were investigated examined using I-V measurements under a solar simulator. Complexes 3 and 5 showed very low series resistance resulting in high rectification ratios which are promising results for the future electronic and photoelectronic applications. (C) 2017 Published by Elsevier GmbH.Öğe Electrical and photoelectrical properties of Ag/n-type Si metal/semiconductor contact with organic interlayer(Elsevier Science Sa, 2015) Ozerden, Enise; Ocak, Yusuf Selim; Tombak, Ahmet; Kilicoglu, Tahsin; Turut, AbdulmecitElectrical and photoelectrical features of Metal/Organic Interlayer/Inorganic Semiconductor (MIS) Schottky device were investigated by using current-voltage (I-V) and capacitance-voltage (C-V) measurements at room temperature. For this purpose, 9,10-dihydrobenzo[a]pyrene-7(8H)-one (9,10-H2BaP) thin film was used as organic interlayer between Ag metal and n-Si semiconductor. Firstly, optical properties of the organic thin film were determined from optical absorption spectrum, and its optical band gap was found to be 3.73 eV. Then, the electrical parameters of the Ag/9,10-H2BaP/n-Si diode such as ideality factor (n), barrier height (Phi(b(I-V))), diffusion potential (V-d), barrier height (Phi(b(C-V))) and carrier concentration (N-d) were calculated from I-V and C-V characteristics at room temperature. The Fb values obtained from both measurements were compared with each other. Besides, the effect of light on I-V measurements of the structure was examined at illumination intensities ranging from 40 to 100 mW/cm(2) with 20 mW/cm(2) intervals using a solar simulator with AM1.5 filter. Light sensitivity, open circuit voltage (V-OC) and short circuit current (I-SC) parameters of Ag/9,10-H2BaP/n-Si structure were calculated from under light measurements. (C) 2015 Elsevier B.V. All rights reserved.Öğe Electrical Characterization of Au/Quercetin/n-Si Heterojunction Diode and Optical Analysis of Quercetin Thin Film(Amer Inst Physics, 2016) Tombak, Ahmet; Ozaydin, C.; Boga, M.; Kilicoglu, T.Quercetin (3,5,7,3',4'-pentahydroxyflavone, QE), one of the most widely distributed flavonoids in fruits and vegetables, has been reported to possess a wide variety of biological effects, including anti-oxidative, anti-inflammatory, anti-apoptosis, hepatoprotective, renoprotective and neuroprotective effects. In this study organic-inorganic junctions were fabricated by forming quercetin complex thin film using spin coating technique on n-Si and evaporating Au metal on the film. Optical properties of quercetin thin film were studied with the help of spectrophotometer. The current-voltage (I-V) characteristic of Au/quercetin/n-Si heterojunction diode was investigated at room temperature in dark. Some basic parameters of the diode such as ideality factor, rectification ratio, barrier height, series resistance and shunt resistance were calculated using dark current-voltage measurement. It was also seen that the device had good sensitivity to the light under 40-100 mW/cm(2) illumination conditions.Öğe Fabrication and electrical properties of an organic-inorganic device based on Coumarin 30 dye(Elsevier Sci Ltd, 2014) Tombak, Ahmet; Ocak, Yusuf Selim; Asubay, Sezai; Kilicoglu, Tahsin; Ozkahraman, FatmaA Coumarin 30/p-Si organic-inorganic device was fabricated by forming a Coumarin 30 thin film on a p-Si semiconductor. The resulting structure had excellent rectifying properties. Electrical parameters of the structure were determined from current-voltage (I-V) measurements in the temperature range 300-380 K. While the barrier height (phi(b)) increased with increasing temperature, the ideality factor and series resistance of the diode decreased. I-V measurements of the structure were also performed under a solar simulator with AM1.5 filter and 100 mW/cm(2) illumination intensity. The structure had 59 mu A short-circuit current and 337 mV open-circuit voltage. Furthermore, capacitance-voltage (C-V) measurements of an Al/Coumarin 30/p-Si diode were carried out at various frequencies. The phi(b), value obtained by using C-V values was compared with that obtained by using I-V data. (C) 2014 Elsevier Ltd. All rights reserved.Öğe Fotovoltaik uygulamalar için üretilen dörtlü yarıiletken filmlerin optik ve yapısal özellikleri(2017) Tombak, Ahmet; Kılıçoğlu, TahsinDünyada enerjiye olan ihtiyaç her geçen gün artmaktadır. Bu ihtiyacın giderilmesinde kullanılan fosil yakıtlar bir yandan tükenirken diğer yandan çevresel felaketlere neden olmaktadır. Bu açıdan yenilenebilir enerjiler içerisinde güneş enerjisi, ihtiyaçların sağlanmasında en önemli aday kaynaktır. Son yıllarda bu konuda oldukça önemli ve heyecan verici çalışmalar yapılmaktadır. Doğada da kayaç halinde bulunan Cu2 ZnSnS (CZTS), kesterit, ticari olarak gittikçe yaygınlaşmaya başlayan Cu(In,Ga)Se24 (CIGS) ince film güneş pillerine en olası alternatif olarak öne çıkmaktadır. Gçerdiği malzemelerin ucuzluğu ve teorik olarak Shockley-Queisser limitinde en uygun bant aralığı olan 1.5 eV luk optik bant aralığı değerine sahip olması ve büyük soğurma katsayısıyla (104 cm-1) CZTS, ince film güneş pili için çok uygun bir soğurucu katman malzemesidir. Cu2CdSnS4 (CCTS) ise 1.37 eV bant aralıklı, 10 4 cm -1 soğurma katsayısına sahip yapısı CTZS’ye benzeyen bir yarıiletkendir. Bu çalışmada güneş pili üretiminde kendine yer bulmaya başlayan ucuz ve bol bulunan malzemelerden Cu2CdSnS4 (CCTS) ve Cu2ZnSnS4 (CZTS) dörtlü yarıiletken filmler, ultrasonik sprey piroliz yöntemleriyle cam altlıklar üzerine üretilmiştir. Gnce filmlerin yapısal özellikleri X ışını kırınımı (XRD), molekül yapısı Raman Spektroskopisi, yüzey morfolojisi taramalı elektron mikroskobu (SEM) ile belirlenmiştir. Güneş pili uygulamasında soğurucu katman olarak kullanılacak filmlerin ışık geçirgenliği ve soğurma özellikleri UV-VIS-NIR cihazı ile belirlendikten sonra optik bant aralıkları tespit edilmiştir. Önemli güneş pili parametrelerinden olan taşıyıcı yük yoğunluğu, iletkenlik tipi ve özdirenç Hall Etkisi ölçüm sistemiyle ölçülerek güneş pili üretimi için en uygun parametreleri taşıyan filmlerden güneş pili üretilmiştir. Anahtar Kelimeler: Dörtlü Yarıiletken, Güneş Pili, Düşük Maliyet, CCTS, CZTS, Ultrasonik SpreyÖğe Güneş pili uygulamaları için dörtlü yarıiletken ince filmlerin ultrasonik sprey yöntemiyle üretilmesi(2016) Ocak, Yusuf Selim; Tombak, Ahmet; Kılıçoğlu, Tahsin[Abstract Not Available]Öğe The influence of substrate temperature on RF sputtered CdS thin films and CdS/p-Si heterojunctions(Elsevier Sci Ltd, 2017) Bozkaplan, Cihat; Tombak, Ahmet; Genisel, Mustafa Fatih; Ocak, Yusuf Selim; Akkilic, KemalCadmium sulfide (CdS) thin films were deposited onto soda lime glasses and p-Si semiconductors at various substrate temperatures (40, 150 and 275 degrees C) by radio frequency (RF) sputtering technique. The effect of substrate temperature on morphological, structural and optical properties of CdS thin films were analyzed by means of atomic force microscopy (AFM), x-ray diffraction (XRD) and uv-vis spectrum data. The results showed that the average roughness (R-a) of thin films increased from 2.0 to 4.0 nm and all films had hexagonal wurtzite structure. The optical band gaps of CdS thin films varied between 2.46-2.43 eV. Characteristic parameters of CdS/p-Si heterojunctions including ideality factor, barrier height, series resistance and rectification ratio were measured. It was seen that both ideality factor and barrier height values of the heterojunctions increase with the increase substrate temperature. It was attributed to increase in inhomogenity of the thin films. Furthermore, the photoelectrical parameters of CdS/p-Si heterojunctions were studied.Öğe Influence of Temperature And Light Intensity on Ru(II) Complex Based Organic-Inorganic Device(Amer Inst Physics, 2016) Asubay, Sezai; Durap, Feyyaz; Aydemir, Murat; Ocak, Yusuf Selim; Tombak, Ahmet; Baysal, AkinAn organic-inorganic junction was fabricated by forming [Ru(Cy2PNHCH2-C4H3O)(eta(6)-p-cymene)Cl-2] complex thin film using spin coating technique on n-Si and evaporating Au metal on the film. It was seen that the structure had perfect rectification property. Current-voltage (I-V) measurements were carried out in dark and under various illumination conditions (between 50-100 mW/cm(2)) and with the temperature range from 303 to 380 K. The structure showed unusually forward and reverse bias temperature and light sensing behaviors. It was seen that the current both in forward and reverse bias increased with the increase in light intensity and temperature.Öğe Modification of electrical and optical properties of CuO thin films by Ni doping(Springer, 2016) Baturay, Silan; Tombak, Ahmet; Kaya, Derya; Ocak, Yusuf Selim; Tokus, Murat; Aydemir, Murat; Kilicoglu, TahsinUndoped and Ni-doped CuO thin films were deposited onto glass substrates using a spin-coating technique at different doping concentrations (undoped, 2, 4, 6, and 10 %). X-ray diffraction patterns for undoped and Ni-doped CuO thin films indicated that the films were polycrystalline, with preferential growth in the (002), (111), and (-311) directions. Atomic force microscopy images revealed that the surface morphologies of the films were not uniform. Scanning electron microscopy images confirmed the presence of agglomerated particles on the surfaces; the coverage increased with the doping level. A Hall effect system with a van der Pauw configuration was used to investigate the electrical properties of the CuO films. The free charge carrier concentration decreased and hole mobility increased with increasing Ni concentration, with the exception of the 10 % Ni-doped CuO sample. Ultraviolet-visible spectroscopy measurements of the film samples indicated an average transmittance of 30-40 % in the visible range. The optical band gap decreased slightly for low-level doping and increased from 2.03 to 2.22 eV for 10 % Ni incorporation. The electrical and optical properties of the CuO films were modified by Ni doping, i.e. the band gap decreased and the mobility increased almost linearly, with the exception of the 10 % Ni-doped sample. SEM images of a undoped b 2 % c 4 % d 6 %, and e 10 % Ni-doped CuO thin films. [GRAPHICS]Öğe n-Type conductivity of CuO thin films by metal doping(Elsevier Science Bv, 2019) Baturay, Silan; Tombak, Ahmet; Batibay, Derya; Ocak, Yusuf SelimDue to its unique electrical and optical properties, copper (II) oxide (CuO) potentially has a wide variety of applications. It is commonly known that CuO has p-type conductivity; however, we report observations of n-type conductivity in thin CuO films by metal doping for the first time. We achieved n-type electrical conductivity in CuO films with cobalt (Co) doping. Undoped and Co-doped CuO thin films were fabricated using a spin coating technique. Electrical parameters, specifically, the charge carrier concentration, sheet resistance, and conductivity type were investigated using a van der Pauw Hall measurement system. By 3 per cent of the cobalt doping conductivity type conversion was observed. The effects of metal doping on the width of the optical band gap were investigated using ultraviolet-visible spectrometry over the wavelength range of 300-1100 nm. The optical band gaps were found to be 1.43, 1.44, 1.44, 1.42 eV for un-doped, 2, 4 and 6% Co doped CuO thin films, respectively. The influence of different concentration ratio on the growth of CuO films was investigated using XRD. Microstrain (e), crystalline size (D) and dislocation density (delta) for all orientations were calculated from XRD analysis. (C) 2017 Elsevier B.V. All rights reserved.Öğe The novel pyridine based symmetrical Schiff base ligand and its transition metal complexes: synthesis, spectral definitions and application in dye sensitized solar cells (DSSCs)(Springer, 2018) Imer, Arife Gencer; Syan, Ranjdar Hamad Basha; Gulcan, Mehmet; Ocak, Yusuf Selim; Tombak, AhmetThe pyridine based azo-linked symmetrical Schiff base ligand, (E)-2,2'-((1E,1'E)-(pyridine-2,6-diylbis(azanylylidene))bis(methanylylidene))bis(4-((E)-phenyldiazenyl)phenol) (H2L), and its Co(II), Ni(II) and Pd(II) transition metal complexes were prepared, and defined by using elemental analysis, Fourier transform infrared, UV-visible, mass, nuclear magnetic resonance spectra, molar conductance, magnetic susceptibility and thermal analysis techniques. The conductivity results pointed out the non-electrolytic nature of all metal complexes. Elemental composition, ultraviolet spectra and magnetic susceptibility data showed that the synthesized complexes are in the binuclear structure and square plane geometry. When compared to the characteristic infrared bands for the functional groups of the ligand structure with complex molecules are reached, the ligand binds to the metal atom via phenolic OH and azomethine-nitrogen. Furthermore, the dye-sensitized solar cells (DSSCs) based on H2L and its metal complexes were fabricated, and photovoltaic properties of these devices were also investigated. The power conversion efficiency of fabricated devices based on ligand H2L can be improved with the incorporation of the transition metal complex.Öğe OPTICAL, ELECTRICAL AND PHOTOELECTRICAL PROPERTIES OF QUERCETIN-CO(II) COMPLEX/N-SI ORGANIC-INORGANIC HYBRID DEVICE(Bilal GÜMÜŞ, 2015) Özaydın, Cihat; Tombak, Ahmet; Boğa, Mehmet; Kılıçoğlu, TahsinQuercetin is a member of the flavonoid’s class and colorful organic molecule widely distributed in nature. Quercetin is known as 2-(3,4-dihydroxyphenyl)-3,5,7-trihydroxy-4H-chromen-4-one with molecular formula C15H10O7. Also, quercetin has conjugated structure with 16 ?-rich electrons. In this study, Quercetin cobalt (II) complex (Quercetin-Co(II) Complex) was synthesized. The thin films of synthesized quercetin cobalt (II) complex were formed on glass and semiconductor substrates by sol-gel spin coating technique. The absorption, reflection and transmittance spectra of the thin film were taken in 200-1100 nm wavelength range. The optical band gap of the film was determined from absorption studies and was found to be 2.59 eV for direct transitions and 1.90 eV for indirect transitions. The morphological properties of the thin film formed on the semiconductor substrates was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). We fabricated Au/Quercetin-Co(II) Complex/n-Si organic-inorganic hybrid device to investigate electrical and photoelectrical properties. The current-voltage (I-V) measurement of the device was carried out at room temperature and in dark. The device has a rectification behavior with the ideality factor n of 1.55 and the barrier height ?b of 0.77 eV. In addition, the short circuit current (Isc) and open circuit voltage (Voc) have been extracted from the I-V measurements under 100 mW/cm2 illumination conditions. Besides, the capacitance-voltage (C-V) characteristics of the device at different frequency and room temperature are discussed.Öğe Optical, Electrical, and Morphological Effects of Yttrium Doping of Cadmium Oxide Thin Films Grown by Ultrasonic Spray Pyrolysis(Springer, 2017) Tombak, Ahmet; Baturay, Silan; Kilicoglu, Tahsin; Ocak, Yusuf SelimCdO films doped with Y concentrations of 0%, 1%, 2%, and 3% were deposited onto soda lime glass using ultrasonic spray pyrolysis. The effect of the doping level on the structural, morphological, optical, and electrical properties of the films was characterized. X-ray diffraction analysis was used to establish that all of the samples were polycrystalline and to determine the structural parameters, i.e., lattice spacing (d), phases and associated (hkl) planes, grain size (D), and dislocation density (delta). The films possessed high conductivity and carrier concentration, showing n-type semiconducting behavior. The films were almost transparent over the range from 600 nm to 1100 nm. The energy bandgap was 2.43 eV, 2.53 eV, 2.68 eV, and 2.70 eV for Y doping of 0%, 1%, 2%, and 3%, respectively. The refractive index and extinction coefficient of the films over the range from 700 nm to 1100 nm were determined by spectroscopic ellipsometry. Atomic force microscopy revealed the effect of Y doping on the surface morphology of the CdO films.
