The purpose of this study is to analyze interface states (N ss ) in Au/TiO 2 (Rutile)/n-Si Schottky barrier diodes (SBDs). TiO 2 was deposited on a n-Si substrate by reactive magnetron sputtering and annealed at 900• C for 4 h in atmosphere to obtain rutile phase

The important structural characteristics of hexagonal GaN in an InGaN/GaN multi quantum well, which was aimed to make a light emitted diode and was grown by metalorganic chemical vapor deposition on c-plain sapphire, are determined by using nondestructive high-resolution X-ray diffraction in detail. The distorted GaN layers were described as mosaic crystals characterized by vertical and lateral coherence lengths, a mean tilt, twist, screw and edge type threading dislocation densities. The rocking curves of symmetric (00.l) reflections were used to determine the tilt angle, while the twist angle was an extrapolated grown ω-scan for an asymmetric (hk.l) Bragg reflection with an h or k nonzero. Moreover, it is an important result that the mosaic structure was analyzed from a different (10.l) crystal direction that was the angular inclined plane to the z-axis. The mosaic structure parameters were obtained in an approximately defined ratio depending on the inclination or polar angle of the sample. © 2009 Springer Science+Business Media, LLC

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Titanium dioxide (TiO 2 ) thin films were deposited on glass substrate by d.c. magnetron sputtering at 200• C substrate temperature. The thicknesses of the films were measured using stylus type profilometer. The deposited films were annealed using rapid thermal annealing (RTA) system in the O 2 ambient for 20 min at 400 and 500• C. Influence of Ar/O 2 flux ratio and annealing temperature on structural and optical properties of the samples was analyzed using X-ray diffraction (XRD) and UV-vis spectrometer in the range of 200-1100 nm. The films annealed above 400• C were crystalline with anatase phase, whereas at the as-deposited states, the films were amorphous. Optical properties such as band gap, refractive index and absorption coefficient were calculated using transmittance spectra of the samples. The influence of thermal annealing on structure and optical properties is discussed. Band gap energies of the TiO 2 films were also determined using photoluminescence(PL) measurements.

Electrical transport data for Al rich AlGaN layers grown by metal-organic chemical vapor dep osition (MOCVD) are presented and analyzed in the temperature range 135-300 K. The temperature depen dence of electrical conductivity indicated that conductivity in the films was controlled by potential barriers caused by carrier depletion at grain boundaries in the material. The Seto's grain boundary model provided a complete framework for understanding of the conductivity behavior. Various electrical parameters of the present samples such as grain boundary potential, donor concentration, surface trap density, and Debye screening length were extracted.