Sürdürülebilir Kalkınma Amaçları
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- MakaleAçık Erişim2015Scopus SJRQ3Influence of RF power on optical and surface properties of the ZnO thin films deposited by magnetron sputtering
Pat, Suat; Şenay, Volkan; Özen, Soner; Korkmaz, Şadan; Geçici, Birol
The influences of the effects of sputtering power on the optical and structural properties of ZnO thin films were investigated. The ZnO layers were deposited on glass slides by RF magnetron sputtering. RF sputtering powers were adjust to 150 W and 250 W. Optical analysis and tools and methods were used for the comparison of the optical and surface properties. The results show that sputtering powers have affected the optical and surface properties. The band gap variations of ZnO thin films are observed. The samples are transparent. The roughness values of sample grown at 250 W are increased threefold in comparison with sample grown at 150 W while RF power is increased. Furthermore, surface contact angle was decreased to one-half of its values obtained at low RF power. This value is close to theoretical limit of contact angle. Obtained results show that surface properties of the layers can changed by RF power, but optical properties are slightly different.
AtıfScopus5WoS6OpenAlex6
İncele - MakaleYalnız künye2015Scopus SJRQ3AlGaAs film growth using thermionic vacuum arc (TVA) and determination of its physical properties
Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan
In this research, an AlGaAs film was deposited on a microscope slide by means of the thermionic vacuum arc (TVA) technique which is a novel plasma production technique. AlGaAs structures were grown by this deposition technique for the first time and this process occurred in a very short period of time. In order to characterize the produced film, nano-structural, nano-mechanical, optical, and surface properties were determined by field emission scanning electron microscope (FESEM), atomic force microscope (AFM), X-ray diffractometer (XRD) and interferometer. According to the results of the measurements, the mean thickness value of the produced film was obtained as 1.8 μm. The band gap value was determined as 2eV from the Kubelka-Munk plot. The refractive index value was obtained as approximately 3.4. Hardness value was determined as 2 GPa from the Oliver-Pharr method. All these values are consistent with the reported values in the literature for the AlGaAs films produced by different methods. TVA technique appeared as a suitable and promising technique for the production of AlGaAs films.
AtıfScopus22WoS24OpenAlex24İncele - MakaleYalnız künye2015Scopus SJRQ3Optical and surface properties of LiFePO4 thin films prepared by RF magnetron sputtering
Volkan, Şenay; Özen, Soner; Pat, Suat; Korkmaz, Şadan
LiFePO4 thin films with thickness values of 65 nm and 70 nm were deposited onto glass substrates by RF magnetron sputtering, using a LiFePO4 target in the argon atmosphere. A comprehensive study of the optical properties was performed and the dispersions of the constants were determined. The transmittance and absorbance spectra were measured in the wavelength range of 400-1000 nm. The films showed optical transmittance over 90% in the visible range. The optical band gap value of the films was evaluated as 3 eV. The refractive index value of the films is 1.63 at λ = 550 nm. AFM micrographs indicate smooth surface with low values ofroot mean square roughness. Contact angle measurements of several testing liquids were used to characterize each sample in terms of wettability. The films are hydrophilic as observed from contact angle measurements. The surface free energy of the film surfaces and their components (dispersive and polar) were calculated from the contact angle data using the different theories available in the literature.
AtıfScopus14WoS12OpenAlex15İncele - MakaleAçık Erişim2015Scopus SJRQ2Deposition of a Mo doped GaN thin film on glass substrate by thermionic vacuum arc (TVA)
Özen, Soner; Şenay, Volkan; Pat, Suat; Korkmaz, Şadan
Current research presents a new deposition method for GaN thin films that produces in a very short production time for GaN-based solid-state applications. A Mo doped GaN thin film on a glass substrate was produced by thermionic vacuum arc (TVA) technique. The TVA technique is a novel non-reactive plasma technique. The optical properties were determined by Filmetrics F20 interferometer and UV–Vis double beam spectrophotometer. The surface morphology was analyzed using field emission scanning electron microscopy and atomic force microscopy. The mean thickness value was measured as 100 nm by Filmetrics interferometer. The crystalline structure of the produced thin film has a Wurtzite crystal structure (004) as obtained by X-ray diffraction. Hardness value was determined as 14 GPa with the Oliver–Pharr method. The obtained properties are consistent with the values reported in related literature. The findings indicate that the TVA method provides advantages for optical and industrial applications.
AtıfScopus20WoS20OpenAlex22İncele - MakaleAçık Erişim2015Scopus SJRQ2Direct and fast growth of GaAs thin films on glass and polyethylene terephthalate substrates using a thermionic vacuum arc
Pat, Suat; Korkmaz, Şadan; Özen, Soner; Şenay, Volkan
Using a thermionic vacuum arc, single‐crystal gallium arsenide (GaAs) layers of micron thickness were grown on PET and glass substrates in 2 min. We present a new deposition mechanism and parameters for GaAs thin films produced in a very short time. Crystal direction was found to be (111) plane for the GaAs/PET sample and (022) plane and (133) plane for the GaAs/glass sample, respectively. The average roughness values of the deposited thin films were determined to be approximately 30 nm for GaAs/PET and 60 nm for GaAs/glass. The structures can be seen clearly in field emission scanning electron microscopy and atomic force microscopy. The obtained optical band is nearly the same with literatures values of the GaAs. Although produced structures in different crystal formations, only aggregations dimensions and absorbance of the layers were changed. Obtained refractive index values are nearly same with database info.
AtıfScopus16WoS18OpenAlex16İncele - BildiriYalnız künye2014Scopus SJRQ1ZnO thin film synthesis by reactive radio frequency magnetron sputtering
Şenay, Volkan; Pat, Suat; Korkmaz, Şadan; Aydoʇmuş, Tuna; Elmas, Saliha; Özen, Soner; Ekem, Naci; Balbaʇ, M. Zafer
In this study, ZnO thin films were deposited on glass substrates by reactive RF magnetron sputtering method at argon-oxygen gas mixing (1:1) atmosphere. Some properties of the synthesized films were investigated by interferometry, UV-vis spectrophotometer, atomic force microscopy, and tensiometer. Tauc method was adopted to estimate the optical band gaps. The band gaps of the deposited films were affected by film thickness. We concluded that the surface composition plays a substantial role in the values of the band gaps. Nanocrystalline structures were detected in all produced samples.
AtıfScopus55WoS49İncele