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We have studied the band offset and alignment of pulsed laser deposited Al 2 O 3 /CuGaO 2 and ZnO/CuGaO 2 hetero-structures using photoelectron spectroscopy. Al 2 O 3 /CuGaO 2 interface exhibited a type I band alignment with valance band offset (VBO) of 4.05 eV whereas type II band alignment was observed in ZnO/CuGaO 2 hetero-structure with a VBO of 2.32 eV. Schematic band alignment diagram for the interface of these hetero-structures has been constructed. Band offset and alignment studies of these heterojunctions are important for gaining insight to the design of various optoelectronic devices based on such hetero-structures. [ABSTRACT FROM AUTHOR]

We studied the band offset and alignment of pulsed laser deposited TiO 2 /CuGaO 2 hetero-structure using x-ray photoelectron spectroscopy. Valance band offset (VBO) of TiO 2 /CuGaO 2 interface was calculated using Kraut equation as 2.15 eV, which was in corroboration with VBO obtained directly from valance band onsets. A schematic band alignment diagram for the TiO 2 /CuGaO 2 interface was constructed which showed a type II band alignment with a significant band bending of 0.48 eV. Interface studies of TiO 2 /CuGaO 2 hetero-structure, showing type II band alignment, is important for gaining insight to the design of various photovoltaic devices based on such hetero-structures. [ABSTRACT FROM AUTHOR]

We have grown Ga doped ZnO (GZO) thin films at moderate temperatures with Ga concentrations in the range varying from 0.25 to 3 at.% on sapphire substrates using buffer assisted pulsed laser deposition. Room temperature resistivity measured was ∼5.1 × 10 −5 Ω cm with a electron mobility of ∼41.9 cm 2 /V s for an optimum Ga concentration of ∼0.75 at.% in the GZO films. Buffer assisted growth methodology maintains relatively good crystalline quality of the GZO thin films, thereby improving the electron mobility even at high dopant concentrations. This plays a key role in decreasing the resistivity of GZO films to the aforementioned value, which to the best of our knowledge is the lowest so far. These highly conducting GZO thin films with good mobility are potential candidates for transparent conducting oxide (TCO) applications in various optoelectronic devices. [ABSTRACT FROM AUTHOR]