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Abstract: The model for amorphous semiconductor InSb (a-InSb) was constructed through the first principles calculations, based on the idea of “continuous random networks” (CRN). The results of structural parameters for a-InSb are in agreement with the available data both theoretically and experimentally. The structure of a-InSb is almost tetrahedrally bonded with a perfect average coordination number of four. Due to the influence of the disorders, the density of states for a-InSb has the smearing structure in contrast to crystalline InSb (c-InSb). As a consequence of the induction of disorders, modification phenomena occur at the band edge of a-InSb in contrast to that of c-InSb. [Copyright &y& Elsevier]

Abstract: First-principles calculations have been performed on the C-doped anatase TiO2. The doped TiO2 shows half-metallic properties and a 2.0 μB magnetic moment per cell. The magnetic coupling is closely related to the C–C distance. When the distance is shorter than a typical CC double bond (), the system is nonmagnetic and the dopants tend to form a cluster through a direct CC bonding interaction [Appl. Phys. Lett. 93 (2008) 132507]. When the distance is between 3.8 and , there exists strong ferromagnetic or antiferromagnetic coupling between two C atoms. The ferromagnetic coupling is induced by the bent C–Ti–C unit. When the distance is further increased, the system becomes paramagnetic. [Copyright &y& Elsevier]

In current work, effects of rapid thermal annealing on the interface chemical bonding states, band alignment, and electrical properties of atomic-layer-deposition-derived HfAlO/Al 2 O 3 gate stack on Si substrates have been studied by X-ray photoemission spectroscopy (XPS), UV–Vis transmission spectroscopy, and electrical measurements. XPS analyses have shown that HfAlO alloy and mixed silicate (Hf-Al-O-Si) increase after post-deposition annealing process. By means of UV–Vis transmission spectroscopy measurements, reduction in band gap for 400 o C-annealed sample has been observed. Accordingly, reduction in the valence band offset and increase in the conduction band offset have been detected for HfAlO/Al 2 O 3 /Si gate stack annealed at 400 °C. Various current conduction mechanisms, such as Poole-Frenkel emission, Fowler-Nordheim (FN) tunneling, and space-charge-limited (SCL) conduction, have been analyzed. Detailed electrical measurements reveal that current conduct mechanisms is SCL conduction at lower field region and FN tunneling and SCL conduction are dominant conduction mechanism at higher field region. [ABSTRACT FROM AUTHOR]