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Copyright of Afyon Kocatepe University Journal of Science & Engineering / Afyon Kocatepe Üniversitesi Fen Ve Mühendislik Bilimleri Dergisi is the property of Afyon Kocatepe University, Faculty of Science & Literature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mugla Journal of Science & Technology is the property of Mugla Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cu3SnS4 thin films were deposited on glass substrates using successive ionic layer adsorption and reaction (SILAR) method at room temperature and annealed at different temperatures in the nitrogene atmosphere to investigate the effects of the post-deposition annealing process on the structural and optical properties of the films. Structural, surface morphological, and optical properties of films were analysed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), Raman spectroscopy, and optical absorption measurements. XRD results revealed that the films consisted of a tetragonal Cu3SnS4 phase before annealing, and increasing annealing temperature caused the improvement of crystal structure and the formation of Cu4SnS4, Cu2S and CuS secondary phases. SEM images showed that the films were composed of nanometer-sized randomly shaped particles. EDAX measurements revealed the existence of Cu, Sn and S elements and also showed that the amounts of Sn and S elements decreased with increasing annealing temperature. Raman spectra confirmed the formation of the Cu3SnS4 phase and secondary phases of Cu4SnS4, Cu2S and CuS at high annealing temperatures. From optical absorption measurements, it was determined that the films had direct transitions and the band gap energies decreased from 1.62 eV to 1.47 eV with increasing annealing temperature. [ABSTRACT FROM AUTHOR]

Katma değeri yüksek, ileri teknoloji ve yüksek maliyet gerektiren malzemelere alternatif olarak ince film kaplama yöntemleri ile eşdeğer yüzey özelliklerine sahip ekonomik malzemeler üretilebilmektedir. İnce film biriktirme yapılarak farklı sensörler, fotovoltaik hücreler, elektronik uygulamalar ve filtreler gibi çeşitli teknolojik malzemelerin temelini oluşturan yarı iletken yüzeyler üretmek mümkündür. Çeşitli fosil yakıtlar ve atıkların yanması ile farklı gazlar açığa çıkmaktadır. Çevreye zarar vermekte ve sağlığa olumsuz etkileri olan bu gazların tespit edilmesi gerekmektedir. CuO yarıiletken ince filmler karbondioksit, etanol, amonyak gibi farklı gazların belirlenmesi ve gerekli uyarıların verilmesinde gaz sensörü olarak kullanımı amacı üzerine çalışmalar yapılmaktadır. Bu çalışma kapsamında cam yüzeyler üzerine CuO yarıiletken ince filmler biriktirilerek gaz sensörü olarak kullanımı test edilmiştir. CuO yarı iletken ince filmlerin CO2 gazının tespitinde alternatif bir gaz sensörü olarak kullanılabileceği tespit edilmiştir.

Copyright of International Journal of Engineering Research & Development (IJERAD) is the property of International Journal of Engineering Research & Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Çalışmada Mo folyolar ve cam üzerine DC saçtırma yöntemiyle kaplanmış Mo ince filmler üzerine aynı anda termal buharlaştırma metoduyla CIGS yarıiletken malzemesi biriktirilmiştir. İki grup Mo alt katmanların AFM cihazı ile topoğrafyaları ve ortalama yüzey pürüzlülükleri elde edilmiştir. CIGS ince filmlerin kalınlıkları SEM cihazı ile kesit görüntüleri alınarak, 1,122 µm olarak tespit edilmiştir. Numunelerin XRD ölçümleri alınarak yapısal farklılıkları belirlenmiştir. Mo folyo ve ince film alt katmanı üzerine biriktirilen CIGS ince filmlerin yüzeyinden 5000, 10000, 25000 ve 50000 büyütmelerde SEM görüntüleri alınmıştır. Elde edilen SEM görüntülerinin GLCM metodu ile Haralick doku özellikleri incelenmiş, elde edilen sonuçlar değerlendirilerek alt katman Mo topoğrafyasının CIGS ince filmlerin morfolojisi üzerine etkisi araştırılmıştır. Hesaplanan Haralick doku özelliklerinin görece geniş alanlardan daha küçük alanlara doğru değişimleri değerlendirilmiştir. A grubu numunelerden elde edilen görüntülerde enerji değerinin 0,21 ile 0,54 arasında, karşıtlık değerinin 0,15 ile 0,35 arasında, korelasyon değerinin 0,66 ile 0,65 arasında ve homojenite değerinin 0,82 ile 0,92 arasında değiştikleri tespit edilmiştir. B grubunda aynı doku özelliklerinin farklılık gösterdiği görülmüştür. Alttaş farklılığının yapı ve morfoloji üzerine etkisi, SEM görüntülerinin doku özellikleri farklılıkları ile açıklanmıştır.

Molybdenum (Mo) material is used in many different fields thanks to its unique properties. The compatibility of interface states between layers is investigated using texture analysis of thin films. The textures of the films may change according to the production parameters and subsequent processes. For this reason, it is necessary to determine the ideal production parameters in order to produce Mo thin films with the most suitable texture depending on the usage area. In this study, Mo thin films in BCC structure and (110) plane, which are often desired in CIGS solar cell applications, could be produced. The fabrication was carried out using a bi-layer fabrication strategy to improve the adhesion and electrical conductivity of the Mo film to the substrate surface. Surface, topography and structure analyzes of the produced films were performed with SEM, AFM and XRD systems, and polar figures were obtained by semi-quantitative texture analysis. When the topographic and detailed structural analysis results are compared with each other and with other studies in the literature, the usability of the production parameters revealed in this study has been demonstrated. [ABSTRACT FROM AUTHOR]

Organik-hibrit güneş hücreleri arasında en popüler olan metil amonyum kurşun iyodür (MAPbI3) fazlı perovskit güneş hücreleridir. Bunun nedeni perovskit güneş hücrelerinin sahip oldukları eşsiz özellikler ve yüksek verimlilikleridir. Ancak perovskite güneş hücreleri üretimlerinden hemen sonra verimlilik kaybı yaşamaktadır. Üretim yöntemleri bu verimlilik kaybının nedenlerinden biri olarak gösterilmektedir. Perovskite üretim yöntemleri incelendiğinde spin kaplama, termal buharlaştırma ve termal kimyasal buhar biriktirme (Thermal CVD) en çok kullanılan yöntemler olarak görülmektedir. Damla döküm yöntemi ise bölgesel olarak kristal üretiminde etkili bir yöntem olarak görülmektedir. Bu çalışmada kimyasal buhar biriktirme ve damla döküm yöntemleri birlikte kullanılarak MAPbI3 filmler üretilmiştir. Elde edilen filmlerin morfolojik ve yapısal özellikleri SEM ve XRD yöntemleri kullanılarak belirlenmiştir. Üretilen perovskit filmler su buharına maruz bırakılmıştır. Su buharına bağlı olarak malzemelerde oluşan yaşlanma süreçleri elektriksel iletkenlik yöntemleri ile karakterize edilmiştir.

Copyright of Erzincan University Journal of Science & Technology is the property of Erzincan Binali Yildirim Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mugla Journal of Science & Technology is the property of Mugla Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bilecik Seyh Edebali University Journal of Social Sciences is the property of Bilecik Seyh Edebali University Journal of Social Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Erzincan University Journal of Science & Technology is the property of Erzincan Binali Yildirim Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Erzincan University Journal of Science & Technology is the property of Erzincan Binali Yildirim Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this work, the influence of post-annealing on the structural, morphological, and optical properties of copper selenide thin films deposited on glass substrate by thermal evaporation was investigated in detail. The post-annealing process at different ambient temperatures in a nitrogen atmosphere was applied to thin films deposited at room temperature. The X-ray diffraction (XRD) patterns showed the presence of cubic Cu2-xSe phase, and it was observed that the crystallinity improves with increasing annealing temperature. In addition, it was deduced that the average crystallite size increased with the annealing temperature. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were employed to investigate the surface morphology of thin films. It was seen that all samples have compact and densely packed surface morphology and grains on the surface become larger. Surface roughness increased from 11nm to 53 nm as the annealing temperature increased. On the other hand, the optical properties of as-deposited and annealed thin films were investigated by utilizing a UV-Visible spectrophotometer. The direct bandgap energies of as-deposited and annealed samples were estimated to be 2.34 eV, 2.31 eV, and 2.29 eV by using the well-known Tauc relation, respectively. The direct bandgap energy of thin films was also calculated using the derivative spectroscopy technique. [ABSTRACT FROM AUTHOR]

In this study, the (Lead Sulfide) PbS thin films with one, two, and three layers were fabricated by employing the chemical bath deposition method. Layer by layer production of PbS thin films was realized for the first time as seen in the literature review. For investigating the crystal structures, the X-ray diffraction (XRD) analysis was used. The structural analyses indicated that the crystallite size was decreased from about 40 nm to 8-10 nm depending on the number of layers. The surface micrographs of the films were obtained using scanning electron microscopy (SEM). When the PbS film was obtained in one layer, some cracks, pinholes, and voids were observed on the sample surface. However, no cracks, voids, or pinhole formation were found on the film surface when the films were coated in two and three layers. [ABSTRACT FROM AUTHOR]

In this study, lead sulfide (PbS) films were coated on microscope glass at the substrate temperature of 370±5 °C by ultrasonic chemical spray pyrolysis technique, which is an easy and economical method. The effect of PbS films obtained with different molarity Pb additions on their structural, surface, optical, and electrical properties was investigated. Their optical, structural, surface, and electrical properties were characterized using UV, spectrophotometer, scanning electron microscopy, Atomic force microscopy, and X-ray spectroscopy analyses. From the X-ray diffraction (XRD) analysis, the PbS thin film was found to have a hexagonal structure. The roughness of the PbS thin film was determined by Atomic Force Microscopy (AFM). From the optical absorption spectrum, it was calculated that the PbS thin film has a narrow optic band gap of 1.69-1.89 eV. The thickness values of the produced films were determined using the spectroscopic ellipsometry technique. The Cauchy-Urbach model was used to determine the thickness of the films. The potential for use of PbS films for photovoltaic solar cell applications was investigated. [ABSTRACT FROM AUTHOR]

Objectives: The present study was conducted to compare the characteristics of a thin film containing an astaxanthin-loaded nanoemulsion (TFANE) using two kinds of natural polymers, namely sodium alginate and gelatin. Materials and Methods: An astaxanthin nanoemulsion was prepared by using the self-nanoemulsifying method, followed by incorporation into a polymer matrix system by the solvent casting method to form TFANE. A characteristic comparison between the sodium alginate and gelatin matrix systems was carried out by comparing the physical and mechanical film properties. At the end of the study, in vitro dissolution tests were also assessed. Results: An intraoral film with good physical and mechanical properties containing an astaxanthin-loaded nanoemulsion was developed successfully using a natural polymer matrix system. The film, made from a gelatin matrix system containing an astaxanthin nanoemulsion, was more flexible and harder than films made from a sodium alginate matrix system, where all of the films have ideal characteristics for intraoral delivery. The dissolution test results showed that, with both sodium alginate and gelatin, more than 90% of the drug was released at 15 minutes. Conclusion: Gelatin as a natural polymer appears to be promising for the preparation of an intraoral thin film delivery system. [ABSTRACT FROM AUTHOR]

In this study, TiO2 based thin films were prepared by adding 1%, 3%, 5% and 10% Ca and samples were produced by sol gel spin coating method. While the samples were being produced, coating was carried out using a rotation speed of 1000 rpm and a rotation time of 30 seconds. The coating process was repeated 3 times. Transmittance, absorption and reflection graphs of films were drawn by UV-VIS spectroscopy and optical band gap was calculated. The sample with the lowest forbidden energy range was found to have undoped TiO2 (3.59 eV). The forbidden energy range of the samples was calculated as 3.68, 3.76, 3.74 and 3.77 for Ca contribution at 1, 3, 5 and 10%, respectively. The permeability graphs of the samples were examined and it was determined that the permeability values were between 70% and 90%. When the absorption graph was examined, it was seen that the average absorption in the visible region was in the range of approximately 0.75% to 4.5% due to the high transparency of the samples. Two-dimensional and three-dimensional images of films produced using Atomic Force Microscope (AFM) were analyzed. When the AFM analyzes were examined, it was seen that there were nano-sized grains. Surface properties, reflection, permeability and absorption curves of thin films produced by sol-gel method were examined and at the end of these investigations, it was determined that the surface morphology and optical properties of thin films changed depending on the Ca additive ratio. [ABSTRACT FROM AUTHOR]

In this study, two films were produced by both using sodium sulphide and without sodium sulphide. The produced films were annealed at 400 °C. From the XRD data, it was observed that the intensity of the peaks increased after the annealing. The surface structures of the films were examined with a SEM instrument. With annealing it was understood that the surface structures of the films were completely changed and the holes were disappeared. [ABSTRACT FROM AUTHOR]

Silar metodu kullanılarak 70 °C’de cam alttabanlar üzerine polikristal Cu2O ince filmleri elde edildi. XRD analizleri filmlerin kübik yapıda olduğunu gösterdi ve örgü parametreleri hesaplandı. Filmlerin yüzey morfolojisi alan emisyonlu taramalı elektron mikroskobu (FE-SEM) ile görüntülendi. Filmlerin optik özelliklerini belirlemek için UV/vis spektrofotometresi kullanılmıştır. Filmlerin oda sıcaklığındaki optik geçirgenlik (% T) değerleri 300-1100 nm dalga boyu aralığında belirlenmiştir. Yarıiletken Cu2O ince filmlerinin görünür bölgedeki optik geçirgenlik değerleri %50-70 olarak bulunmuştur. Filmlerin enerji bant aralığı değerleri (Eg) 2.53-2.62 eV bulundu.

Bu çalışmada InGaAsN ince filmler ilk defa farklı bir teknik olan Termiyonik Vakum Ark (TVA) tekniği ile üretilmiştir. InGaAsN ince filmler üretilirken TVA üretim parametreleri belirlenmiştir. İnce filmler üç farklı alt taş üzerine gerçekleştirilmiştir. Bunlar cam, Si ve Polietilen tereftalat (PET) alt taş malzemedir. Üretilen ince filmlerin XRD analizleri ile kristal yapıları aydınlatılmaya çalışılmıştır. Yüzey bileşenleri için EDX analizi kullanılmıştır. Filmlerin yüzey oluşumları atomik kuvvet mikroskobu ile görüntülendi. UV-Vis spektrofotometresi ile elde edilen soğurma değerlerinden ise yapıların yasak enerji aralıkları değerleri incelenmiştir. Sonuçlara göre, farklı alt taşlar üzerine farklı atomik bileşimler elde edilmiştir.

In this study, Cu(In,Ga)(Se1-yTey)2 thin films were obtained by evaporation of the bulk form compound with electron beam followed by annealing at elevated temperature. The X-ray diffraction patterns (XRD), Raman spectra, surface images and atomic concentration measurements of the samples were analyzed and compared with the structural properties of the undoped and low Te doped samples. In XRD patterns, it was observed that a phase separation such as Cu(In,Ga)Se2 and CuIn3Se5 formed in the CIGS thin film, but with the Te content, this phase separation was disappeared. Experimental values of A1 Raman modes of the samples were compared with the values obtained by a theoretical approach. It was seen that the film surface became more uniform and the particles formed in sub-micron dimensions as the Te content increase in the film. Similarly, it was observed that the composition profile in the structure improved (the amount of Ga increased) and that the targeted amount of Te almost entered the structure. [ABSTRACT FROM AUTHOR]

In this study, pH effect was investigated on CdO thin films which were grown by SILAR technique on glass substrates room temperature. X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV vis spectrophotometer measurements were examined for structural, morphological and optical properties of thin films. The XRD results showed that thin films exhibited orientation at different angles and planes at pH 11.5 and higher. SEM images showed significant changes in the surface morphology of the films with the change of pH value. The optical absorption measurements showed that the band gap was increased due to the pH increase. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

SnO2 thin films having tetragonal structure were grown on (100) oriented n-type Si and corning glass substrates at room temperature with RF magnetron sputtering technique. The atomic distribution and interfacial evaluation of the deposited structures were evaluated with the depth profile spectra obtained by the Secondary Ion Mass Spectrometer. It was seen that the atomic distribution of Sn and O showed a uniform distribution throughout the film depth. However, it was precisely determined by SIMS technique that an ultra-thin SiO2 layer was formed between the SnO2 film, which was deposited on Si, and Si substrate. The formed SiO2 interlayer thickness was determined to be dependent on the sputtering kinetics i.e. RF deposition power. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bu çalışmada katkısız CuO ve farklı konsantrasyonlarda Li-katkılı Li-ZnCuO filmler cam altlıklar üzerine SILAR yöntemi ile başarılı bir şekilde büyütüldü. Üretilen bu filmler metalurjik mikroskop (MM), X-ışını kırınımı (XRD) ve UV-Vis. spektroskopi ile karakterize edildi. MM sonuçları, CuO filmlerin morfolojisi üzerine Li-Zn ikili katkılama konsantrasyonunun önemli bir etkiye sahip olduğunu gösterdi. XRD verileri filmlerin nanoboyutta kristalize olduklarını ve kristallenme kalitesinin katkı konsantrasyonuna bağlı olarak değiştiğini açığa çıkardı. Uv-Vis. analiz sonuçları, filmlerin hem optik bant aralığı değerlerinde hem de geçirgenliklerinde katkı konsantrasyonuna bağlı olarak önemli farklılıkların oluştuğunu ortaya koydu.

Transition metal oxides (TMOs) are of great interest for their catalytic stability and semi-conductive properties. For supercapacitor electrodes, TMOs are used to alternative materials due to the enhancement of energy density and specific capacitance. In this study, molybdenum trioxideoctadecylamine (MoO3-ODA) and molybdenum trioxide- EOnPOmEOn-type block-copolymer composite thin films on ITO were prepared by Spin Coating method. MoO3-ODA/ITO and MoO3- Pluronic®F127/ITO electrodes were fabricated with above mentioned thin films and their electrochemical properties were investigated. Our results demonstrated that electrical conductivity increased in the presence of ODA and Pluronic®F127 (EO106PO70EO106). Furthermore, molybdenum trioxide composite structure prepared with Pluronic®F127 shown better electrochemical energy storage capacity. Our electrochemical studies and results show that MoO3 composite structures with Pluronic®F127 can be a promising approach to fabricate new generation high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Structural, morphological and optical properties of (Gallium Selenide) GaSe thin films grown on glass and gallium selenide single crystal substrates with Modified Chemical Bath Deposition (M-CBD) method have been investigated by using XRD, AFM and UV-Vis techniques. XRD measurements showed that GaSe thin films grown on glass and GaSe single crystal substrates were at rhombohedral and hexagonal structures, respectively. The average particle sizes of GaSe thin films grown on glass and GaSe single crystal substrates were determined form AFM images as 33.2 nm and 35.3 nm, respectively. It was observed that the particle sizes of films grown on both glass and GaSe substrate increased while the band gaps decreased with annealing. Urbach energies of GaSe thin films grown on glass substrates were found to be bigger than Urbach energies of GaSe thin films grown on GaSe single crystal substrates. [ABSTRACT FROM AUTHOR]

Ac charge transport mechanisms have been comparatively investigated in ZnO thin films having different Cu dopant. A comparative study of the applicability of quantum mechanical tunelling and correlated barrier hopping model to obtained ac electrical conductivity results has been performed. Comparing the temperature dependence of the frequency exponent shows that the correlated barrier hopping model best describes the experimental data on the ac conductivity in ZnO:Cu thin films. In order to gain an understanding of the applicability of Meyer-Neldel rule, the dependence of the thermal activation energy on Cu doping concentration in these films has also been studied. The obtained experimental results indicated that Meyer-Neldel rule can be succesfully applied ac conductivity data for highly Cu doped films but not others which has been explained on the basis of distribution variations in density of states. [ABSTRACT FROM AUTHOR]

Chemical bath deposition (CBD) method was used to deposit thin films of PbS. In the experiments, PbS was obtained at four temperatures which are 55, 65, 75 and 85 °C. The effects of relatively high temperature were investigated in detail. The structural properties of the PbS films were examined by using X-ray diffractometer (XRD). According to the XRD, it was found that when temperature was increased, the preferred orientation shifted from (111) plane to the (002) plane at a deposition temperature higher than 75 °C. Besides, crystallite sizes (cs), lattice constants (a), average stresses (S), micro strains (ε) and dislocation densities (δ) were obtained from the XRD results. Surface properties of the PbS thin films were researched by using scanning electron microscope (SEM). It was seen from the SEM images that there was crack on the surface of the films when the film was obtained at 55 °C. On the other hand, no cracks were observed in the SEM images of PbS films of 30000 magnifications produced at temperatures higher than 55 °C. [ABSTRACT FROM AUTHOR]

In this study, the effect of zinc oxide (ZnO) coating amount on the efficieny of n-type zinc oxide/p-type silicon (n-ZnO/p-Si) heterojunction solar cell was investigated. ZnO nanoparticles were synthesized by sol gel method. The synthesized nanoparticles were coated on glass substrates and p-Si substrates using spin coating method. The coating process was carried out in different amounts as 2, 4, 5 and 15 times. After the coating process, the thin film coated substrates were placed in a square furnace and annealed at 500 °C for 30 min. Structure characterization and surface morphology were analyzed using X-ray diffraction (XRD) method and scanning electron microscopy (SEM). For each n- ZnO/p-Si heterojunction solar cell structure, short circuit current (Isc) and open circuit voltage (Voc) were determined by electrical measurements and efficiency (η) calculations were made. All processes were performed at room temperature. According to this study, the efficiency of solar cells increases with increasing the amount of ZnO coating up to a critical thickness and decreases when the critical thickness is exceeded (due to the more ZnO coating). From this it was concluded that the amount of ZnO coating (ZnO layer thickness) is an important parameter affecting the performance of solar cells. [ABSTRACT FROM AUTHOR]

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Abstract: In this study, properties of thermally evaporated polycrystalline CdInTe thin films were investigated. The surface morphology, composition and crystal structure of the films were determined by means of SEM, EDXA and XRD analysis. Temperature dependent Hall effect measurements were carried out in the temperature range of 200-400 K. In the whole temperature region, the dominant transport mechanism of the films was found to be thermionic emission of the carriers over the grain boundaries. The room temperature conductivity, mobility and electron concentration values were found to be 1.8x10-2 (ï—.cm)-1, 50 cm2V-1s-1 and 1.1x10-15 cm-3, respectively. The mobility-temperature dependence showed that ionized impurity, neutral donor impurity and acoustic phonon scattering mechanisms were effective over the low (216-256 K), intermediate (256-317 K) and high temperature (317-357 K) regions, respectively. The optoelectronic properties of the films were also investigated by absorption in 190-1100 nm wavelength region and photoconductivity measurements in 80-400 K temperature range. Key words: Semiconductors, thin films, thermal evaporation, Hall effect Termal Buharlaştırma ile Büyütülmüş Polikristal CdInTe İnce Filmlerin Yapısal, Elektriksel ve Optik Özelliklerinin Araştırılması Özet: Bu çalışmada, termal buharlaştırma yoluyla üretilmiş polikristal CdInTe ince filmlerin özellikleri araştırılmıştır. Filmlerin yüzey morfolojisi, kompozisyonu ve kristal yapısı SEM, EDXA ve XRD analizleri ile incelenmiştir. Sıcaklığa bağlı Hall etkisi ölçümleri 200-400 K sıcaklık aralığında gerçekleştirilmiştir. Tüm sıcaklık aralığında etkin akım mekanizmasının termoiyonik emisyon olduğu tespit edilmiştir. Oda sıcaklığında iletkenlik, mobilite ve elektron konsantrasyonu sırasıyla 1.8x10-2 (ï—.cm)-1, 50 cm2V-1s-1 ve 1.1x10-15 cm-3 olarak bulunmuştur. Mobilite-sıcaklık değişimi ölçümlerinden iyonize safsızsızlık, nötral verici safsızlığı ve akustik fonon saçılma mekanizmalarının sırasıyla (216-256 K), (256-317 K) ve (317-357 K) sıcaklık aralıklarında etkin olduğu belirlenmiştir. Filmlerin optoelektronik özellikleri 190-1100 nm dalgaboyu aralığında soğurma ve 80-400 K sıcaklık aralığında fotoiletkenlik ölçümleri ile araştırılmıştır. Anahtar kelimeler: Yarıiletken, ince film, termal buharlaştırma, Hall etkisi