In this paper, we report the effect of 1.5 MeV proton beam irradiation dose on the structural and electrical properties of TiO 2 thin films deposited on n-Si substrates. The formation and transformation of different TiO 2 phases in the irradiated thin films were characterized by X-ray diffraction and X-ray photoelectron spectroscopy (XPS). X-ray diffraction measurements revealed that the as grown film was rich in Ti 5 O 9 phase and then converted to mixed phases of TiO 2 (rutile and anatase) after exposure with radiation doses up to 5 Â 10 14 cm À2 . The XPS results revealed the formation of oxygen vacancy (negative) traps in the exposed TiO 2 films, which showed strong dependence on the dose. The C-V measurements showed that proton radiations also damaged the Si substrate and created deep level defects in the substrate, which caused a shift of 0.26 6 0.01 V in the flat band voltage (V FB ). I-V measurements showed that the ideality factor increased and the rectification ratio dropped with the increase in the radiation dose. The present study showed the stability of TiO 2 /Si interface and TiO 2 film as an oxide layer against proton radiations. V C 2014 AIP Publishing LLC. [http://dx.

Atomic layer deposited (TiO2)x(Al2O3)1−x/In0.53Ga0.47As gate stacks for III-V based metal-oxidesemiconductor field-effect transistor applications

Abstract. Most of the rotating or noting patterns are being developed by using silver plating through chemical coating. Silver layers deteriorate with the passage of time and become less reflective while undergo through cleaning process due to its softness and the results become unpredictable. In this paper an alternate method for development of above mentioned pattern has been demonstrated. Chromium (Cr) and Silver (Ag) thin films of 200nm and 160nm thick respectively have been realized using electron beam evaporation (PVD technique) on quartz substrate. Structural analysis has been carried out by XRD and SEM while optical transmission/reflection has been studied using spectrophotometer. XRD analysis shows that Ag coated thin films exhibit FCC structure while Cr coated thin films reveals a BCC structure. SEM analysis shows almost smooth and uniform surfaces in both cases. After passing through high and low temperature cycles it was found that the results of pattern structures developed by chromium coating were more reliable than obtained through silver platting process.

Charge accumulation at interfaces is a key issue for the use of high dielectric constant materials in nanoelectronics. In this work, we report the charge accumulation behavior at the TiO 2 /n-Si interfaces formed at various growth temperatures. Growth of TiO 2 in an oxygen deficient environment led to the formation of rutile phase in the as-grown films. The anatase phase was recovered by annealing in air and the ratio of anatase to rutile phase in the TiO 2 films improved considerably. The amount of charge accumulation and the direction of charge injection were studied by obtaining C-V hysteresis curves in the as-grown and the annealed TiO 2 films. It was observed that the amount of accumulated charges decreased as the density of interface border traps dropped considerably due to annealing. X-ray photoelectron spectroscopy revealed the presence of two major phases corresponding to TiO 2 and Ti 2 O 3 , due to the existence of oxygen deficiencies. The annealing in air resulted in appreciable increase in the weight percentage of TiO 2 phase in samples grown at high temperatures. The healing of oxygen vacancies improved with the increase in the weight percentage of TiO 2 . Thus, it was concluded that the accumulated charges were mainly due to oxygen deficiencies and the healing of oxygen defects led to a drop in the interface charges, thus, bringing the interface close to ideal. V C 2012 American Institute of Physics. [http://dx.

We have employed technology computer-aided design -a Synopsys Õ tool to carry out a comparative study of the electrical behaviour of the metal-insulatorsemiconductor Schottky diodes with different metal contacts (Ag, Au, Pt and Cr), on n-Si(100). We employed physics models to determine the Shockley-Read-Hall (SRH) and Auger recombination rates as a function of electric field profile in the depletion region. An insight was obtained as variation in the electric field at the metal-semiconductor interface due to work function variation affected the current mechanisms and recombination rates. The results were compared with the existing models. On the basis of analysis, merits and demerits of Schottky junctions formed due to these metals are discussed. The ideality factor of Au and Pt was found to be just around 2.0, while it was higher for Cr and Ag. However, the barrier height in the case of Cr was small, thus making it another possible metal layer for the Schottky contact. Similarly, SRH recombination rates were almost negligible for Au and Pt metal layer and became appreciable for Cr and much higher in Ag, making it not a good choice for the Schottky contact.