Al-doped ZnO films were grown on glass substrates by the pulsed-laser deposition technique with varying substrate temperatures. The optical band gap decreases from 3.64 to 3.46 eV as the substrate temperature increases from 350 to 450 • C, illustrating the increase in Al content in the context of a degenerate semiconductor, and can be explained in the framework of the Burstein-Moss effect. All films show optical transparency greater than 85%. Al:ZnO films show a metal-semiconductor transition to metal-like behavior as the substrate temperature increases from 350 to 450 • C. The observed metal-like and metal-semiconductor transitions are explained by taking into account the Mott phase transition and localization effects due to defects. The resistivity decreases from 896 to 470 µ cm as the substrate temperature increases from 350 to 450 • C. In addition, the competition between the thermally activated carriers and scattering effects of free carriers in a degenerate semiconductor can also explain the metal-semiconductor transition.

A comprehensive microstructural study was conducted on optimally-doped epitaxial Ba(Fe 1 −x Co x ) 2 As 2 thin films grown by pulsed laser deposition on various substrates of a wide range of lattice constants: SrTiO 3 , LaAlO 3 , (La,Sr)(Al,Ta)O 3 , MgO, CaF 2 , and BaF 2 . We found that epitaxial strain directly affects the superconductivity in the film, with the transition temperature decreasing linearly with increasing in-plane lattice constant of the film. However, the strain is not determined by the lattice mismatch between the film and substrate. Instead, the mosaic spread of the grain orientation in the film and the thermal expansion coefficient of the substrate were found to correlate well with the in-plane lattice constant of the film. The result confirms the importance of structural distortions to the superconductivity in the Ba(Fe 1−x Co x ) 2 As 2 films.

Concept mapping has been traditionally used as a tool for active learning, student's learning assessment and evaluation. In an attempt to achieve student learning, curricula development and assessment have taken new and diverse approaches. Concept mapping is one novel way for curricula development and validation of program outcomes and their linkages with required skills and competencies' levels. Mechanical, Chemical, and Computer Engineering have used concept maps across a wide range of educational applications: from simply creating a conceptual overview of course objectives for students to using them for curricula evaluation and improvement.This paper reports on the use of concept maps for both extremes. The paper presents a review of concept mapping applications in engineering disciplines in general and in Electrical and Computer Engineering in specific. The generic concept map framework is presented and its expansion into the specific mapping for the authors' affiliated University's baccalaureate engineering degrees is presented. The validation process of the curriculum map is discussed. The impact of the conceptual presentation of the curriculum to freshman and sophomore students is measured through surveys and the data is discussed.

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We report on the ultraviolet ͑UV͒-radiation sensing of pulsed-laser deposited In 2 O 3 : SnO 2 : ZnO films grown on glass substrates. The films demonstrate sharp increase ͑ϳ0.35 ⍀͒ in electrical resistance on UV illumination. The resistance of the films shows strong spectral ͑in the vicinity of 325 nm͒ and power dependence. This is explained due to the presence of defects located at lattice disorders that generate levels within the semiconductor band gap and originate depletion region around them when charged. This reduces the effective conduction region, increasing the effective resistance. These results show new possibilities for the low-cost high performance UV radiation sensors for biosafety.