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Article Citation - WoS: 6Citation - Scopus: 6Gold and Ytterbium Interfacing Effects on the Properties of the Cdse/Yb Nanosandwiched Structures(Elsevier Science Bv, 2018) Alharbi, S. R.; Qasrawi, A. F.Owing to the performance of the CdSe as an optoelectronic material used for the production of quantum dots, photosensors and wave traps we here, in this article, report the enhancements in structural and electrical properties that arises from the nanosandwiching of a 40 nm thick Yb film between two films of CdSe (CYbC-40). The CdSe films which were deposited onto glass, Yb and Au substrates are characterized by X-ray diffraction, temperature dependent electrical conductivity and impedance spectroscopy measurements in the frequency range of 10-1800 MHz. The analysis of the XRD patterns have shown that the glass/CdSe/Yb/CdSe films exhibit larger grain size and lower strain, defect density and lower stacking faults compared to the not sandwiched CdSe. In addition, it was observed that the Yb shifts the donor states of the n-type CdSe from 0.44 to 0.29 eV leading to a modification in the built in voltage of the material. On the other hand, the design of the energy band diagram has shown the ability of the formation of the Au/CYbC-40/Yb as Schottky (SB) and the Au/CYbC-40/Au as back to back Schottky barriers (BBSB). While the SB device show low band pass filter characteristics, the BBSB device performed as band stop filters. The BBSB device exhibited negative capacitance effects with filtering features that reveal a return loss of 42 dB at similar to 1440 MHz.Article Citation - WoS: 18Citation - Scopus: 18Fabrication of Al/Mgo and C/Mgo Tunneling Barriers for Tunable Negative Resistance and Negative Capacitance Applications(Elsevier Science Bv, 2013) Qasrawi, A. F.In this work, the design and characterization of magnesium oxide based tunneling diodes which are produced on Al and InSe films as rectifying substrates are investigated. It was found that when Al thin films are used, the device exhibit tunneling diode behavior of sharp valley at 0.15 V and peak to valley current ratio (PVCR) of 11.4. In addition, the capacitance spectra of the Al/MgO/C device show a resonance peak of negative capacitance (NC) values at 44.7 MHz. The capacitance and resistance-voltage characteristics handled at an ac signal frequency of 100 MHz reflected a build in voltage (V-bi) of 1.29 V and a negative resistance (NR) effect above 2.05 V. This device quality factor (Q)-voltage response is similar to 10(4). When the Al substrate is replaced by InSe thin film, the tunneling diode valley appeared at 1.1 V. In addition, the PVCR, NR range, NC resonance peak, Q and lib; are found to be 135, 0.94-2.24 and 39.0 MHz, similar to 10(5) and 1.34 V, respectively. Due to the wide differential negative resistance and capacitance voltage ranges and due to the response of the C/MgO/InSe/C device at 1.0 GHz, these devices appear to be suitable for applications as frequency mixers, amplifiers, and monostable-bistable circuit elements (MOBILE). (c) 2013 Elsevier B.V. All rights reserved.Article Citation - WoS: 20Citation - Scopus: 26Simplified software inspection process in compliance with international standards(Elsevier Science Bv, 2009) Mishra, Deepti; Mishra, AlokA significant amount of software is developed all over the world by small and medium size software organizations. These organizations do not have enough infrastructures and resources to implement an austere quality plan. Software inspection is a fundamental component of the software quality assurance process. Formal review methods are rigorous and their implementation is cumbersome for small and medium enterprises. In this paper, we have presented a new simplified inspection process which is easy to implement. requires fewer resource and almost no documentation. Also, people who are conducting this inspection need not be present at the same place during most stages of the inspection process. We have also compared this process with IEEE and NASA standards for software inspection and found that it meets almost 99% of both standards. While there has been much research on inspection, little attention is paid towards compliance with international standards. These results could be used as a basis for further research in software inspection and process towards aligning with international standards. This process has been successfully implemented in a CMM level 3 software development organization which is striving to accomplish higher maturity levels to establish at the international level. (C) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 20Citation - Scopus: 21On Global Asymptotic Stability of 2-D Discrete Systems With State Saturation(Elsevier Science Bv, 2008) Singh, VimalA criterion for the global asymptotic stability of 2-D discrete systems described by the Roesser model employing state saturation nonlinearities is presented. The criterion is a less restrictive version of an earlier criterion due to Liu and Michel. (C) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 9Citation - Scopus: 9Design and Characterization of Au/In4< Field Effect Transistors(Elsevier Science Bv, 2018) Khusayfan, Najla M.; Qasrawi, A. F.; Khanfar, Hazem K.In the current work, the structural and electrical properties of the In4Se3/Ga2S3 interfaces are investigated. The X-ray analysis which concern the structural evolutions that is associated with the substrate type has shown that the hexagonal kappa-In2Se3 and the selenium (rhombohedral) rich orthorhombic In4Se3 phases of InSe are grown onto glass and gold substrates, respectively, at substrate of temperature of 300 degrees C in a vacuum media. The coating of the kappa-In2Se3 and of In4Se3 with amorphous layer of Ga2S3 is accompanied with uniform strain. The In4Se3/Ga2S3 interface is found to be of attractive quantum confinement features as it exhibited a conduction and valence band offsets of 0.20 and 1.86 eV, respectively. When the Au/In4Se3/Ga2S3 interface was contacted with carbon metallic point contact, it reveals a back to back Schottky hybrid device that behaves typically as metal-oxidesemiconductor field effect transition (MOSFET). The depletion capacitance analysis of this device revealed built in voltage values of 1.91 and 1.64 V at the Au and C sides, respectively. The designed MOSFET which is characterized in the frequency domain of 0.01-1.80 GHz is observed to exhibit, resonance-anti-resonance phenomena associated with negative capacitance effect in a wide domain of frequency that nominate it for applications in electronic circuits as parasitic capacitance minimizer, bus switching speed enhancer and low pass/high pass filter at microwave frequencies. (C) 2018 The Authors. Published by Elsevier B.V.Article Citation - WoS: 6Citation - Scopus: 8Topological Derivative Based Optimization of 3d Porous Elastic Microstructures(Elsevier Science Bv, 2014) Ozdemir, IzzetAs an alternative to the well established microstructural optimization techniques, topological derivative based optimization framework has been proposed and successfully implemented for tailoring/optimizing 2D elastic composites recently, Amstutz et al. [1]. In this paper, an optimization framework for 3D porous elastic microstructures is presented which is based on the notion of topological derivative and the computational homogenization of elastic composites. The sensitivity of the homogenized elasticity tensor to the insertion of infinitesimal hollow spheres within the elastic microstructure is used as the measure for the finite element based evolutionary optimization algorithm. The capabilities of the proposed framework, which is free of any regularization parameter, is assessed by means of example problems including some comparisons with analytical bounds. (C) 2013 Elsevier B.V. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 7Temperature-Dependent Electrical Resistivity, Space-Charge Current and Photoconductivity of Ga0.75in0.25< Single Crystals(Elsevier Science Bv, 2013) Isik, M.; Gasanly, N. M.Dark electrical resistivity, space-charge-limited (SCL) current and photoconductivity measurements were carried out on Ga0.75In0.25Se single crystals. Analysis of the dark resistivity measurements revealed the presence of one level with activation energy of 0.10 eV. Current voltage characteristics showed that both ohmic and SCL characters exhibit in 180-300 K range. Analysis of the experimental data in the SCL region resulted with a trap level at 0.11 eV above the valence band. Photoconductivity measurements were performed at different light intensities in the temperature range of 150-300 K. Behavior of the recombination mechanism in the crystal was brought out as sublinear recombination from the dependence of photocurrent on illumination intensity. Moreover, obtained activation energies were compared with the results of other experimental techniques applied to Ga0.75In0.25Se crystals in literature. (C) 2013 Elsevier B.V. All rights reserved.Article Citation - WoS: 35Citation - Scopus: 39Metric-Like Spaces To Prove Existence of Solution for Nonlinear Quadratic Integral Equation and Numerical Method To Solve It(Elsevier Science Bv, 2018) Hazarika, Bipan; Karapinar, Erdal; Arab, Reza; Rabbani, MohsenThe purpose of this paper is to obtain some common fixed point results for two mappings satisfying various contractive conditions in metric-like spaces. These results extend some previous results in the literature, since the condition under which the operator admits common fixed points is more general than the others in literature. Therefore, several well known results are generalized. As an application we use these results to existence of solution for nonlinear quadratic integral equation. To credibility, we apply modified homotopy and Adomian decomposition method to find solution of the above problem with high accuracy. (C) 2017 Elsevier B.V. All rights reserved.Article Citation - WoS: 171Citation - Scopus: 191Coincidence Point Theorems on Metric Spaces via Simulation Functions(Elsevier Science Bv, 2015) Roldan-Lopez-de-Hierro, Antonio-Francisco; Karapinar, Erdal; Roldan-Lopez-de-Hierro, Concepcion; Martinez-Moreno, JuanDue to its possible applications, Fixed Point Theory has become one of the most useful branches of Nonlinear Analysis. In a very recent paper, Khojasteh et al. introduced the notion of simulation function in order to express different contractivity conditions in a unified way, and they obtained some fixed point results. In this paper, we slightly modify their notion of simulation function and we investigate the existence and uniqueness of coincidence points of two nonlinear operators using this kind of control functions. (C) 2014 Elsevier B.V. All rights reserved.Article Citation - WoS: 7Citation - Scopus: 7In situ monitoring of the permanent crystallization, phase transformations and the associated optical and electrical enhancements upon heating of Se thin films(Elsevier Science Bv, 2019) Qasrawi, A. F.; Aloushi, Hadil D.In this work, the in situ structural transformations from amorphous to polycrystalline upon heating and the associated enhancements in the structural parameters of selenium thin films are studied by means of X-ray diffraction technique. The Se thin films which are grown onto ultrasonically cleaned glass substrate by the thermal evaporation technique under vacuum pressure of 10(-5) mbar exhibits structural transformation from amorphous to polycrystalline near 353 K. The films completed the formation of the structure which includes both of the hexagonal and monoclinic phases at 363 K. It is observed that the hexagonal phase dominates over the monoclinic as temperature is raised. Consistently, the thermally assisted crystallization process is accompanied with increase in the crystallite size, decrease in the microstrain, decrease in defect density and decrease in the percentage of stacking faults. The scanning electron microscopy measurements also confirmed the crystallinity of selenium after heating. The time dependent reputations of the crystallization test has shown that the achieved phase transitions and enhancements in structural parameters are permanent in selenium. Optically, the crystallization process is observed to be associated with redshift in the absorption spectra and in the value of the energy band gap. Electrically, the in situ monitoring of the electrical conductivity during the heating cycle has shown that the electrical conductivity stabilizes and exhibit a decrease in the acceptor levels from 566 to 321 meV after the crystallization was achieved.
