Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleYalnız künye2017Scopus SJRQ2The Al doping effect on the surface, optical, electrical and nanomechanical properties of the ZnO and AZO thin films prepared by RF sputtering technique
Pat, Suat; Mohammadigharehbagh, Reza; Özen, Soner; Şenay, Volkan; Yudar, H. Hakan; Korkmaz, Şadan
In this study, ZnO and aluminum doped ZnO (AZO) thin films were deposited at constant RF power of 100 W for the determine of the structural, surface, optical, electrical and nanomechanical properties. X–Ray diffraction (XRD), atomic force microscopy (AFM), nanoindentation technique and UV–Vis spectrophotometer were used. ZnO (100) and ZnO (004) orientations were detected in the ZnO and AZO films. The crystallite size values for the films were calculated as to be as 35 nm and 20 nm for ZnO and AZO thin films, respectively. It was found that the roughness values decreased to 3.15 nm from 5.15 nm for AZO and ZnO films, respectively. The hardness values of the ZnO and AZO thin films are measured as 7 GPa and 11 GPa. Young's modulus values were determined as 155 GPa and 95 GPa for ZnO and AZO films, respectively. The ZnO and AZO thin films have high transparency.
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İncele - MakaleYalnız künye2016Scopus SJRQ1Optical, structural, morphological and compositional characterization of a Co-doped GaAs semiconducting thin film produced by thermionic vacuum arc
Şenay, Volkan; Özen, Soner; Pat, Suat; Korkmaz, Şadan
A 80 nm 2 at% Co-doped GaAs thin film was deposited on a glass substrate under a high vacuum condition by means of the thermionic vacuum arc technique using GaAs and Co pellets as source materials. Tools and techniques such as an optical reflectometer, XRD, UV-VIS-NIR spectrophotometer, FESEM, EDX, and AFM were employed to investigate some of the physical properties of the produced film. From the optical investigations, the refractive index at 632.8 nm and optical band gap of the film were determined to be 3.60 and 1.42 eV respectively. XRD characterization indicated that the film contained GaAs and Co phases. A uniform surface morphology with fine grain covering the entire surface was observed through the FESEM and AFM studies, while 30 nm grain size and 2.72 nm root mean square roughness were obtained. The EDX analysis also confirmed the presence of Ga, As and Co in the film.
AtıfScopus19WoS17OpenAlex18İncele - MakaleYalnız künye2016Scopus SJRQ2Optical and surface properties of optically transparent Li3PO4 solid electrolyte layer for transparent solid batteries
Pat, Suat; Özen, Soner; Şenay, Volkan; Korkmaz, Şadan
In this study, optical and surface properties of the optically transparent Li3PO4 solid electrolyte layer for transparent solid battery have been investigated for the first time. To determine the optical properties, transmittance, absorbance, reflection, refractive index spectra, and optical band gap were determined by UV-Vis spectrophotometer and optical interferometer. The surface property of the transparent Li3PO4 solid electrolyte was analyzed using atomic force microscopy. One another important parameter is contact angle (CA) surface free energy (SFE). CA and SFE were determined by optical tensiometer. These values probably are a most important parameter for polymer and hybrid battery performance. For the best performance, value of CA should be low. As a result, solid electrolyte layer is a highly transparent and it has a high wettability. SCANNING 38:317–321, 2016.
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İncele - BildiriYalnız künye2016Some physical properties of Co-doped GaAs thin films grown by thermionic vacuum arc
Şenay, Volkan; Özen, Soner; Pat, Suat; Korkmaz, Şadan; Mohammadigharehbagh, Reza; Akkus, B.; Dogan, G.S.; Mutlu, R.B.C.; Yalcin, L.S.; Oktem, Y.
Cobalt doped GaAs thin films with the thickness of 100 nm and 200 nm were deposited on glass substrates by a thermionic vacuum arc system. The optical and surface properties were investigated as functions of the film thickness. The refractive index of the films decreased with the increasing thickness. A band gap value of 1.42 eV was obtained for the 100 nm film and 1.38 eV for the 200 nm film from the Tauc plots of (αhν)2 vs. hν. According to the results obtained from the AFM studies, the root mean square surface roughness of the films were nm and 3.13 nm for the 100 nm and 200 nm film, respectively.
AtıfScopus1WoS1OpenAlex1İncele - BildiriYalnız künye2016Investigation of the surface free energy of the ITO thin films deposited under different working pressure
Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan; Akkus, B.; Dogan, G.S.; Mutlu, R.B.C.; Yalcin, L.S.; Oktem, Y.
This study discusses the influence of working pressure on the surface energy of the ITO thin films produced by radio frequency magnetron sputtering method. Optical tensiometer (Attension Theta Lite) is used for evaluating wetting behavior of the water droplet on the film surface and Equation of State method was selected to determine surface free energy for this study. Equation of state method does not divide the surface tension into different components such as polar, dispersive, acid-base. It is calculated the surfaces' free energy measuring the contact angle with a single liquid. The surface free energy value was in the range of 15-31 mN/m. Also, the transmittances were determined in the wavelength range between 200 and 1000 nm using the UNICO 4802 UV-Vis double beam spectrophotometer. Transmittances of the produced ITO thin films are greater than %70 in the visible range.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2016Scopus SJRQ2Comparisons of surface and optical properties of the heavily carbon-doped GaN nanocrystalline films deposited by thermionic vacuum arc method
Pat, Suat; Özen, Soner; Şenay, Volkan; Korkmaz, Şadan
In this paper, heavily C-doped GaN samples were deposited on glass and PET substrates by the thermionic vacuum arc (TVA) method, for the first time. Microstructure, surface and optical properties of the carbon-doped GaN samples were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy, atomic force microscopy, and UV–Vis spectrophotometer. According to XRD pattern, fullerene (C60) structures were able to deposit in doped samples, for the first time. The fullerene structures were detected at heavily carbon-doped GaN. The obtained band gap changes of heavily carbon-doped GaN samples are determined. The band gap of CGaN on PET substrate decreased to a lower value, about 100 meV. The band gaps were shifted to the lowest wavelengths towards the edge of the UV region by heavily doped carbon. (002) and (004) peaks for GaN were also detected.
AtıfScopus6WoS5OpenAlex7İncele - MakaleAçık Erişim2016Scopus SJRQ2Optical and surface properties of the in doped GaAs layer deposition using thermionic vacuum arc method
Pat, Suat; Özen, Soner; Şenay, Volkan; Korkmaz, Şadan; Şimşek, Veli
A broadband optical transparent InGaAs semiconductor layer production of micron thicknesses was produced in only 75 s by thermionic vacuum arc (TVA) method at the first time. The optical and surface properties of the produced layers have been investigated. InGaAs structure is using in electronics and optoelectronics devices. The main advantage of TVA method is its fast deposition rate, without any loss in the quality of the films. Doping is a very simple and fast according to common production methods. InGaAs is an alloy of indium arsenide (InAs) and gallium arsenide (GaAs). InAs with (220) crystallographic direction and GaAs with (024)/(022) crystallographic directions were detected using by XRD analysis. GaAs and InAs are in the cubic and zinc blende crystal system, respectively. According to the transmittance spectra, sample has a broadband transparency in the range of 1000–3300 nm. According to results, defined TVA method for In doping to GaAs is proper fast and friendly method. SCANNING 38:297–302, 2016.
AtıfScopus1WoS1OpenAlex3İncele - MakaleYayıncıda açık erişim2016Scopus SJRQ2The influence of voltage applied between the electrodes on optical and morphological properties of the InGaN thin films grown by thermionic vacuum arc
Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan
The aim of this research is to investigate the optical and morphological properties of the InGaN thin films deposited onto amorphous glass substrates in two separate experiments with two different voltages applied between the electrodes, i.e. 500 and 600 V by means of the thermionic vacuum arc technique. This technique is original for thin film deposition and it enables thin film production in a very short period of time. The optical and morphological properties of the films were investigated by using field emission scanning electron microscope, atomic force microscope, spectroscopic ellipsometer, reflectometer, spectrophotometer, and optical tensiometer. Optical properties were also supported by empirical relations. The deposition rates were calculated as 3 and 3.3 nm/sec for 500 and 600 V, respectively. The increase in the voltage also increased the refractive index, grain size, root mean square roughness and surface free energy. According to the results of the wetting experiments, InGaN samples were low-wettable, also known as hydrophobic. SCANNING 38:14-20, 2016.
AtıfScopus22WoS23OpenAlex25İncele - BildiriYalnız künye2016Impedance analysis of nano thickness layered AlGaN acoustic sensor deposited by thermionic vacuum arc
Özen, Soner; Bilgiç, Eyüp; Gülmez, Gülay; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan; Mohammadigharehbagh, Reza; Akkus, B.; Dogan, G.S.; Mutlu, R.B.C.
In this study, AlGaN acoustic sensor was deposited on aluminum metal substrate by thermionic vacuum arc (TVA) method for the first time. Gallium materials are used in many applications for optoelectronic device and semiconductor technology. Thermionic vacuum arc is the deposition technology for the variously materials and applications field. The thickness of the acoustic sensor is in deposited as nano layer. Impedance analyses were realized. Also, TVA production parameters and some properties of the deposited layers were investigated. TVA is a fast deposition technology for the gallium compounds and doped gallium compounds. Obtained results show that AlGaN materials are very promising materials. Moreover, these acoustic sensors have been produced by TVA technology.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2016Scopus SJRQ2Optical, morphological and mechanical properties of an Al-Al2O3 nanocomposite thin film grown by thermionic vacuum arc
Şenay, Volkan; Özen, Soner; Pat, Suat; Korkmaz, Şadan
An Al-Al2O3 nanocomposite thin film was deposited onto a glass substrate in high vacuum condition using Al2O3 pellets as source material by means of the thermionic vacuum arc technique in just 50 s. UV-visible spectrophotometer, optical reflectometer, spectroscopic ellipsometer, XRD, FESEM and AFM were employed to investigate the optical, structural morphological and mechanical properties of the produced film. The film exhibited a high transmittance (above 80%) in the 400-1000 nm region. The dispersion of the refractive index was discussed in terms of the single oscillator model. The optical band gap value derived from the Wemple-DiDomenico dispersion relationship was 5.7 eV. It was observed that the results of the optical investigations agreed well with Al2O3 thin films. XRD characterization showed that the film contained Al and Al2O3 phases. The FESEM analysis revealed that the film morphology had a dense characteristic. 2D and 3D AFM micrographs indicated a smooth surface with a low value of average roughness. When compared to the mechanical properties of Al2O3 thin films, it was observed that the hardness and Young's modulus reduced due to presence of ductile Al particles.
AtıfScopus9WoS8OpenAlex11İncele - MakaleAçık Erişim2016Scopus SJRQ1Heavily carbon doped GaAs nanocrystalline thin film deposited by thermionic vacuum arc method
Pat, Suat; Korkmaz, Şadan; Özen, Soner; Şenay, Volkan
In this paper, we introduced a new different thin film deposition method for heavily carbon doped GaAs. Used method is thermionic vacuum arc (TVA) and first used for the carbon doping process. The method is very fast deposition process for the other growth method such as metal organic chemical vapor deposition, molecular beam epitaxy, molecular organic molecular beam epitaxy. The smallest grain size of GaAs and doped GaAs were obtained by carbon doping process. Mean crystalline size and height of crystalline size were found to be 3.4 nm and 4 nm, respectively. Crystal direction was found to be (022) plane and (024) plane for the sample at 45.322° and 75.060°, respectively. The production process and obtained results show that used methods is very simple, low cost, eco friendly and very fast method for the carbon doped GaAs.
AtıfScopus9WoS9OpenAlex10İncele - BildiriYalnız künye2016Investigation of the thickness effect to impedance analysis results AlGaN acoustic sensor
Özen, Soner; Bilgiç, Eyüp; Gülmez, Gülay; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan; Mohammadigharehbagh, Reza; Akkus, B.; Dogan, G.S.; Mutlu, R.B.C.
In this study, AlGaN acoustic sensors were deposited on aluminum metal substrate by thermionic vacuum arc (TVA) method, for the first time. Impedance analyses of the fabricated acoustic sensors were investigated for the determining of effect of the nano layer thickness. Thickness values are very close to each others. Fabricated sensors have been fabricated from AlGaN deposited on aluminum substrates. Gallium materials are used in many applications for optoelectronic device and semiconductor technology. Thermionic vacuum arc is the deposition technology for the variously materials and applications field. TVA production parameters and some properties of the deposited layers were investigated. TVA is the fast deposition technology for the gallium compounds and doped gallium compounds. Obtained results that AlGaN layer are very promising material for an acoustic sensor but also TVA is proper fast technology for the production.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2016Scopus SJRQ1Optical, morphological properties and surface energy of the transparent Li4Ti5O12 (LTO) thin film as anode material for secondary type batteries
Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan
LTO thin film was deposited for the first time on a glass microscope slide (MS) by RF magnetron sputtering technology. This method has been suitable for preparation of high-quality thin films. The surface properties of the produced film were determined by atomic force microscope (AFM). The surface of the produced film appeared smooth and homogeneous. LTO coated on MS had compact structure and low roughness. A UV-vis spectrophotometer was used to determine intensity of light passing through the samples. Thus, according to the results obtained the produced film was highly transparent. The refractive index of the LTO thin film was presented in a low MSE value by spectroscopic ellipsometry (SE) and it was about 1.5. The optical band gap (Eg) was determined by the Tauc method. The produced LTO thin film exhibited a wide band gap semiconductor property with a band gap energy of about 2.95 eV. Finally, the surface free energy of the LTO thin film was calculated from the contact angle measurements using the Lewis acid-base, OWRK/Fowkes, Wu and Zisman methods.
AtıfScopus24WoS23OpenAlex27İncele - MakaleYalnız künye2016Scopus SJRQ2Morphology, composition, structure and optical properties of CuO/Cu2O thin films prepared by RF sputtering method
Korkmaz, Şadan; Geçici, Birol; Korkmaz, S. Deniz; Mohammadigharehbagh, Reza; Pat, Suat; Özen, Soner; Şenay, Volkan; Yudar, Hafizittin Hakan
In this paper, copper oxide (CuO/Cu2O) nanocrystalline thin films were deposited by radio frequency (RF) magnetron sputtering system at 75 W and 100 W. The surface, optical, composition and structural properties of obtaining samples were characterized by using atomic force microscopy (AFM), UV–Vis spectrophotometer, field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The optical band gaps of produced films were calculated as 2.05 eV and 1.83 eV for 75 W and 100 W. The layer's thicknesses were measured as 20 nm and 50 nm using a Filmetrics F20. FESEM images of the samples prove the AFM images change and also show homogeneity of thin films and variation relative to power change, thus revealed the surface of samples disturb in homogen mode. EDX results denote presence of Cu and O elements inside the deposited samples.
AtıfScopus56WoS52OpenAlex56İncele - MakaleYalnız künye2016Scopus SJRQ2Surface and optical properties of indium tin oxide layer deposition by RF magnetron sputtering in argon atmosphere
Yudar, H. Hakan; Korkmaz, Şadan; Özen, Soner; Şenay, Volkan; Pat, Suat
This study focused on the characterization and properties of transparent and conductive indium tin oxide (ITO) thin films deposited in argon atmosphere. ITO thin films were coated onto glass substrates by radio frequency (RF) magnetron sputtering technique at 75 and 100 W RF powers. Structural characteristics of producing films were investigated through X-ray diffraction analysis. UV–Vis spectrophotometer and interferometer were used to determine transmittance, absorbance and reflectance values of samples. The surface morphology of the films was characterized by atomic force microscope. The calculated band gaps were 3.8 and 4.1 eV for the films at 75 and 100 W, respectively. The effect of RF power on crystallinity of prepared films was explored using mentioned analysis methods. The high RF power caused higher poly crystallinity in the produced samples. The thickness and refractive index values for all samples increased respect to an increment of RF power and were calculated as 20, 50 nm and 1.71, 1.86 for samples at 75 and 100 W, respectively. Finally, the estimated grain sizes for all prepared films decreased with increasing of 2θ degrees, and the number of crystallite per unit volume was calculated. It was found that nearly all properties including sheet resistance and resistivity depend on the RF power.
AtıfScopus11WoS10OpenAlex11İncele - MakaleYalnız künye2015Scopus SJRQ3A study on optical, morphological and mechanical properties of Al2O3 ultra-thin films deposited by RF reactive magnetron sputtering
Pat, Suat; Özen, Soner; Şenay, Volkan; Aydoʇmuş, Tuna; Elmas, Saliha; Korkmaz, Şadan; Ekem, Naci; Balbaʇ, M. Zafer
The Al2O3 ultra-thin films with the thicknesses of 30 nm and 35 nm were deposited on glass microscope slides by a radio frequency reactive magnetron sputtering system. The optical, morphological and mechanical properties were investigated as function of the film thickness. The refractive index of the resulting Al2O3 ultra-thin film increased with the increasing thickness. Both the films showed high transparency of > 85% and low reflectivity of < 10% in the visible and near infrared region. A band gap of ∼8.65 eV was obtained for the 30 nm film and ∼7.53 eV for the 35 nm film from an empirical relation between refractive index and band gap. According to the results obtained from the AFM studies, the root mean square surface roughness of the films are 3.67 nm and 3.77 nm for the 30 nm and 35 nm film, respectively. The hardness and Young modulus values decreased with the increasing film thickness.
AtıfScopus8WoS7İncele - MakaleAçık Erişim2015Scopus SJRQ2Characterization of a fast grown GaAs:Sn thin film by thermionic vacuum arc
Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan
In this research, a tin doped gallium arsenide thin film was grown on a glass substrate by means of the TVA technique in a very short period of time (70 s) and it’s morphological, compositional, and optical properties were examined. The deposited GaAs:Sn structures were characterized via both atomic force microscope (AFM) and field emission scanning electron microscope (FESEM). In this context, current research aims to reach a conclusion about the structure of the produced GaAs:Sn film by combining AFM, FESEM and energy dispersive X-ray spectroscopy data. From the optical investigation, the refractive index and extinction coefficient values for the produced film were obtained as 3.68 and 0.03 at the wavelength of 632.8 nm, respectively. The direct optical band gap energy of the deposited thin film was determined by two different models. Estimated optical band gap values were compared with each other. The results showed that TVA technique is suitable for a GaAs:Sn coating on glass substrate.
AtıfScopus6WoS5OpenAlex6İncele - MakaleYalnız künye2015Scopus SJRQ2Some physical properties of a Si-doped nano-crystalline GaAs thin film grown by thermionic vacuum arc
Şenay, Volkan; Özen, Soner; Pat, Suat; Korkmaz, Şadan
Abstract A 160 nm thick Si-doped nano-crystalline GaAs film was grown on a glass substrate by means of the thermionic vacuum arc in just 50 s. Tools and techniques such as an optical reflectometer, Uv-Vis-NIR spectrophotometer, XRD, FESEM, AFM, Hall effect measurement, and diiodomethane, ethylene glycol, formamide, and water contact angle measurements were employed to investigate some of the physical properties of the produced film. XRD characterization indicated that the film contained GaAs (hexagonal system in atomic ratio of 1) and SiAs (monoclinic system in atomic ratio of 1) phases. The grain size obtained from Scherrer's Formula was in the range of 30-40 nm. The AFM micrographs showed the film topography, revealing a surface root mean square roughness of 14.5 nm and average height of 48.3 nm. From the wetting experiments, it was found that the contact angle value is strongly dependent on the liquid used.
AtıfScopus20WoS18OpenAlex21İncele - MakaleYalnız künye2015Scopus SJRQ2GaN thin film deposition on glass and PET substrates by thermionic vacuum arc (TVA)
Pat, Suat; Korkmaz, Şadan; Özen, Soner; Şenay, Volkan
In this paper, GaN thin film production was realized by thermionic vacuum arc (TVA), a plasma deposition technique, for the first time. We present a new deposition mechanism for GaN thin films with a very short production time. Microstructure properties of samples were analyzed by X-ray diffractometry. The peak at 2θ = 72.88° corresponding to GaN (0004) was detected in XRD spectra. The surface morphology of the deposited GaN films was analyzed using field emission scanning electron microscopy and atomic force microscopy. The surface properties of the produced samples are quite different. The average roughness values were determined to be 0.48 nm for GaN/PET and 1.17 nm for GaN/glass. The optical properties (i.e., refractive index and reflection) were determined using an interferometer. Moreover, the obtained optical data were compared with bulk GaN materials. The refractive indexes were measured as 2.2, 3,0 and 2,5 for the GaN/glass, GaN/PET and bulk GaN, respectively. The transparencies of the different GaN-coated substrates are nearly the same. The obtained band gap values were measured in the energy range of 3.3-3.5 eV. TVA is a novel non-reactive plasma technique for the generation of metal organic thin films. The main advantage of this method is its fast deposition rate without any loss in the quality of the films.
AtıfScopus32WoS31OpenAlex34İncele - MakaleAçık Erişim2015Scopus SJRQ1Investigation on the morphology and surface free energy of the AlGaN thin film
Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan
The purpose of this paper is to analyze surface properties of AlGaN thin film produced using thermionic vacuum arc technique. Thermionic vacuum arc is an alternative deposition technique for GaN thin films that produces in a very short production time for GaN-based solid-state applications. XRD results showed that AlGaN thin film with cubic crystal structure on a amorphous glass was grown. Conductivity type of AlGaN thin film is determined as p-type by hot-probe method which is a very simple method. The surface morphology was analyzed and discussed using field emission scanning electron microscopy (FESEM) and atomic force microscopy. The contact angles in four different testing liquid and surface free energy of the AlGaN thin film were investigated by optical tensiometer.
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