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Article Citation - WoS: 26Citation - Scopus: 27Impact of Yb, In, Ag and Au Thin Film Substrates on the Crystalline Nature, Schottky Barrier Formation and Microwave Trapping Properties of Bi2o3< Films(Elsevier Sci Ltd, 2017) Khusayfan, Najla M.; Qasrawi, A. F.; Khanfar, Hazem K.The effect of the Yb, In, Ag and Au thin film metal substrates on the structural and electrical properties of Bi2O3 thin films are investigated by means of X-ray diffraction, impedance spectroscopy an current-voltage characteristic techniques. The Bi2O3 films are observed to exhibit a crystallization nature depending on the crystal structure of the substrate. Particularly, when the metal substrate is facing centered cubic, the Bi2O3 prefers the gamma-phase of body centered cubic crystallization for the (Yb, Ag and Au)/Bi2O3 interfaces. Whereas when a tetragonal substrate (indium) is used, the tetragonal beta-Bi2O3 single phase is preferred. All structural parameters presented by the lattice constant, degree of orientation, dislocation density, micro-strain and grain size are observed to strongly depend on the crystal type. In addition, the evaluation of the Schottky barrier formation at the (Yb, In, Ag, Au)/Bi2O3/Au interfaces by the current-voltage characteristics, revealed that the (In, Au)/Bi2O3/Au interface exhibit ohmic nature of contact and the (Yb,Ag)/Bi2O3/Au are of Schottky type, the rectification ratio for the Yb/Bi2O3/Au interface reaches a value of 10(5) indicating the applicability of these interfaces in CMOS digital logic devices. Moreover, the impedance spectroscopy analysis revealed that the ohmic interfaces exhibit a negative capacitance effect. The In/beta-Bi2O3/Au and Yb/.-Bi2O3/Au interfaces are performing as microwave traps with wave absorption percentage of 62% and 92% at frequencies of 193 and 1200 MHz, respectively. The features of the devices are promising as they indicate the applicability as microwave resonator and fast electronic switches.Article Citation - WoS: 11Citation - Scopus: 13Low Temperature Crystallization of Amorphous Silicon by Gold Nanoparticle(Elsevier, 2013) Karaman, M.; Aydin, M.; Sedani, S. H.; Erturk, K.; Turan, R.Single crystalline Si thin film fabricated on glass substrate by a process called Solid Phase Crystallization (SPC) is highly desirable for the development of high efficiency and low cost thin film solar cells. However, the use of ordinary soda lime glass requires process temperatures higher than 600 degrees C. Crystallization of Si film at around this temperature takes place in extremely long time exceeding 20 h in most cases. In order to reduce this long process time, new crystallization techniques such as Metal Induced Crystallization (MIC) using thin metal films as a catalyst layer is attracting much attention. Instead of using continuous metal films, the use of metal nanoparticles offers some advantages. In this work, gold thin films were deposited on aluminum doped zinc oxide (AZO) coated glass and then annealed for nanoparticle formation. Amorphous silicon was then deposited by e-beam evaporation onto metal nanoparticles. Silicon films were annealed for crystallization at different temperatures between 500 degrees C and 600 degrees C. We showed that the crystallization occurs at lower temperatures and with higher rates with the inclusion of gold nanoparticles (AuNP). Raman and XRD results indicate that the crystallization starts at temperatures as low as 500 degrees C and an annealing at 600 degrees C for a short process time provides sufficiently good crystallinity. (c) 2013 Elsevier B.V. All rights reserved.
