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تسجيل مستخدم جديدPt, Ni and Ti Schottky barrier contacts to {beta}-(Al0.19Ga0.81)2O3 grown by Molecular Beam Epitaxy on Sn doped {beta}-Ga2O3 substrate
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A comprehensive current-voltage (I-V) characterization is performed for three different Schottky contacts; Pt, Ni and Ti, to unintentionally doped (UID) {beta}-(Al0.19Ga0.81)2O3 grown by molecular beam epitaxy (MBE) on {beta}-Ga2O3 for temperatures ranging between 25C -300C. Reciprocal space mapping shows the (Al0.19Ga0.81)2O3 films are strained and lattice matched to the substrate. Schottky Barrier Height (SBH), ideality factor (n), and series resistance (Rs) are extracted from the I-V characteristics for the three types of metals and temperatures. Room temperature capacitance-voltage (C-V) measurements revealed fully depleted {beta}-(Al0.19Ga0.81)2O3 layer. Extracted room temperature SBHs after zero field correction for Pt, Ni and Ti were 2.39 eV, 2.21 eV, and 1.22 eV respectively. Variation of SBHs with metal clearly indicates the dependence on work function.
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