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Article Citation - WoS: 3Citation - Scopus: 3Characterization of As2se3< Heterojunction Designed for Multifunctional Operations(Iop Publishing Ltd, 2021) Qasrawi, A. F.; Kayed, T. S.In this article, As2Se3/MoO3 heterojunction devices are structurally, compositionally, optically and electrically characterized. The heterojunction devices which are prepared by the thermal evaporation technique under vacuum pressure of 10(-5) mbar are observed to exhibit amorphous nature of growth. The optical spectrophotometry measurements and analyses on the heterojunction devices revealed a conduction and valence band offsets of values of 2.64 and 4.08 eV, respectively. In addition, the dielectric dispersion and the optical conductivity parametric analyses have shown that the heterojunction could exhibit large drift mobility value up to 73.7 cm(2) V-1 s(-1). From electrical point of view, while the capacitance- voltage curves reveal characteristics of MOSFET devices, the current--voltage curves display tunneling diode characteristics. The features of the As2Se3/MoO3 devices including the band offsets, drift mobility, plasmon frequency, microwave band filtering and MOSFET characteristics make them attractive for use as thin films transistors suitable electrical and optical applications.Article Citation - WoS: 16Al/Moo3< Broken Gap Tunneling Hybrid Devices Design for Ir Laser Sensing and Microwave Filtering(Ieee-inst Electrical Electronics Engineers inc, 2020) Qasrawi, Atef F.; Khanfar, Hazem K.Herein the design of broken gap heterojunction devices made of molybdenum trioxide and zinc phthalocyanine coated onto Al substrates are reported. The devices which are prepared by the thermal evaporation technique under vacuum pressure of 10(-5) mbar are observed to exhibit a conduction and valence band offsets of 3.36 and 3.56 eV, respectively. The heterojunction devices are observed to form a subband gap of 0.66 eV between the valence bands edges of p- ZnPc and conduction bands edges of p-MoO3 leading to a p(+)/n(+) heterojunction type. Analysis of the current-voltage characteristics of the devices has shown that it exhibits tunneling diode characteristics with maximum tunneling barriers of width of similar to 45 nm. The device displayed biasing dependent photosensitivity in response to 850 nm laser lights. In addition to its characteristics as MOS device, when it was imposed with ac signals in the frequency domain of 0.01-1.80 GHz, it displayed resonance-antiresonancephenomena accompanied with negative capacitance effect in the studied range of spectra. The analysis of the alternating current (ac) electrical conductivity has shown that the ac conduction is mostly governed by quantum mechanical tunneling assisted with correlated barriers hopping. The laser light photosensitivity, the negative capacitance effect, the capacitance switching within 100 ns and the bandpass characteristics with notch frequency of 1.24 GHz make the Al/MoO3/ZnPc/Al attractive for use as IR sensors, parasitic capacitance cancellers, fast capacitance switches and microwave bandpass filters.Article Citation - WoS: 7Citation - Scopus: 8Nonlinear Optical Performance of Cdo/Inse Interfaces(Iop Publishing Ltd, 2020) AlGarni, Sabah E.; Qasrawi, A. F.In this article, the growth nature, structural and optical properties of CdO/InSe interfaces are investigated. The CdO/InSe interfaces are prepared by the thermal vacuum deposition technique. Structurally, while the CdO exhibited cubic structure, the InSe layer was amorphous in nature. The morphological analyses have shown that the interface is composed of randomly distributed circular grains of average sizes of similar to 170 nm. The interfacing of the CdO and InSe resulted in enhancing the light absorbability of CdO by similar to 21 times in the IR range. It also showed well aligned conduction bands and valence band offset of 0.72 eV. The Drude-Lorentz modeling of the imaginary part of the dielectric spectra of the CdO/InSe interfaces has shown that the device is suitable for the fabrication of field effect transistors. The drift mobility of free carriers at the interface reached 42.27 cm(2)/Vs. In addition, a quality factor larger than 10(3) is achieved in the IR range indicating the suitability of these optical interfaces to store electromagnetic energy. These properties are important as they shows the applicability of the CdO/InSe interface in solar cells and optoelectronics as optical signal receivers or converters.
