Mutlu Kundakçı

Characterization of CuInS2 Thin Films with Different Cu/In Ratio

Thin films of CuInS2 were grown on glass substrate by successive ionic layer adsorption and reaction method with different [Cu]/[In] ratios and annealed at 400 °C for 30 min. The crystal structure and grain sizes of the thin films were characterized by X-ray diffraction method. Atomic force microscopy was used to determine surface morphology of the films. Optical and electrical properties of these films were investigated as a function of [Cu]/[In] ratios. The electrical resistivity of CuInS2 of thin films was determined using a direct current-two probe method in the temperature range of 300–470 K. It is observed that, the electrical resistivity values show a big decreasing with increasing [Cu]/[In] ratio. Hence, the [Cu]/[In] ratio in the solution can drastically affect the structural, electrical, and optical properties of thin films of CuInS2.

InGaN thin film deposition on Si(100) and glass substrates by termionic vacuum arc

Group-III nitride semiconductors covering infrared, visible and ultraviolet spectral range has direct band gaps changing from 0,7 eV (InN) to 3,4 eV (GaN). LEDs emit red, blue, green light, ultraviolet (UV) laser diodes (LD), UV light detectors and high power electronic devices are obtained and commercialized based on group-III nitride materials. InGaN semiconductor can be deposited by different techniques such as molecular beam epitaxy (MBE), metal organic chemical vapor deposition (MOCVD). In this study, InGaN thin films were prepared on Si and glass substrates as well as on GaN layer by termionic vacuum arc (TVA) which is a plasma asisted thin film deposition technique. The film was deposited at 10-6 torr working pressure, 18A filament current. Plasma was produced at 200 V with 0,6A plasma current. The purpose of this research is to investigate the properties of InGaN thin films. X-ray diffraction (XRD) spectrophotometer was used to analyze microstructure of the deposited films. Scanning electon microscopy (SEM) were used for surface morphology characterizations. Compositional analysis was done by energy dispersive X-ray spectroscopy (EDAX).

A comparison study of Co and Cu doped MgO diluted magnetic thin films

Transition metal-doped MgO diluted magnetic thin films are appropriate candidates for spintronic applications and designing magnetic devices and sensors. Therefore, MgO:Co and MgO:Cu films were deposited on glass substrates by Chemical Spray Pyrolysis (CSP) method different thin film deposition parameters. Deposited different transition metal doped MgO thin films were compared in terms of optic and structural properties. Comparison optic analysis of the films was investigated spectral absorption and transmittance measurements by UV-Vis double beam spectrophotometer technique. Comparison structural analysis of the thin films was examined by using XRD, Raman Analysis, SEM, EDX and AFM techniques. The transition metal-doped; MgO:Co and MgO:Cu thin films maybe have potential applications in spintronics and magnetic data storage.

Some of structural and morphological optimization of GaN thin film on Si(100) substrate grown by RF sputter

One of important material of III-nitrides can be said to be GaN with direct-wide band gap (~ 3.4 eV) and many industrial devices such as solar cell, LED has been based on GaN thin film. In this research, we elaborately investigated growth of GaN thin film on Si(100) substrate by RF sputter technique and characterization of the film. We have successfully grown GaN thin film on Si substrate with hexagonal structure which has been confirmed by analysis of X-ray measurements. Also, we obtained structural properties of GaN film by (XRD) X-ray Diffraction measurements depending on different Argon, nitrogen and RF power values. During experiment, the value from 25sccm to 100sccm Argon gas value, the value from 0sccm to 4sccm Nitrogen gas value and from 50 watt to 125 watt RF power value has been applied. Among these values, we determined the best film in terms of crystalline structure of film. From AFM results, we attained and analyzed average roughness (Ra), maximum peak height (Rp), and maximum depth (Rv), ave...

Magnetic, optical and structural characterization of ZnO:Co; ZnO:Fe thin films

Co-doped ZnO and Fe-doped ZnO diluted magnetic semiconductor films were prepared on glass substrates by chemical spray pyrolysis (CSP) method. Synthesized ZnO:Co and ZnO:Fe thin films by CSP method were compared to thin film properties. Optical analysis of the synthesized thin films was examined by spectral absorption and transmittance measurements using UV-Vis double beam spectrophotometer technique and Photoluminescence (PL) spectroscopy. Structural characterizations of the thin films were examined by using X-ray diffraction (XRD), Raman Analysis, field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM) techniques, respectively. Magnetic properties of the films investigated by Vibrating sample magnetometer (VSM) measurements and magnetization measurements of thin films were compared.VSM measurements of ZnO:Co and ZnO:Fe thin films showed that ferromagnetic behavior for each thin films.