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A review is given of the future device processing needs for Ga2O3 power electronics. The two main devices employed in power converters and wireless charging systems will be vertical rectifiers and metal oxide semiconductor field effect transistors (MOSFETs). The rectifiers involve thick epitaxial layers on conducting substrates and require stable Schottky contacts, edge termination methods to reduce electric field crowding, dry etch patterning in the case of trench structures, and low resistance Ohmic contacts in which ion implantation or low bandgap interfacial oxides are used to minimize the specific contact resistance. The MOSFETs also require spatially localized doping enhancement for low source/drain contact resistance, stable gate insulators with acceptable band offsets relative to the Ga2O3 to ensure adequate carrier confinement, and enhancement mode capability. Attempts are being made to mitigate the absence of p-type doping capability for Ga2O3 by developing p-type oxide heterojunctions with n-type Ga2O3. Success in this area would lead to minority carrier devices with better on-state performance and a much-improved range of functionality, such as p-i-n diodes, Insulated Gate Bipolar Transistors, and thyristors. [ABSTRACT FROM AUTHOR]

Manganese-doped zinc oxide (Mn-doped ZnO) thin films were prepared using chemical bath deposition (CBD), and the impacts of the manganese dopant concentration on the structure, electrical resistivity, optical transmission, and magnetic properties were investigated using x-ray diffractometry, Hall-effect measurements, ultraviolet-visible-near-infrared (UV-Vis-IR) spectrophotometry, and vibrating sample magnetometry (VSM), respectively. The concentration of the manganese dopant in the ZnO thin film critically impacted the resulting properties, and the 4.0 at.% Mn-doped ZnO film had a resistivity of 5.8 × 10 Ωcm, transmittance of 75.6% in the visible light range, and bandgap of 3.30 eV when the film was annealed at 600°C in an Ar + H atmosphere. Annealing the film could enhance its magnetic properties such that the film had a saturation magnetization of 21.0 emu/cm and a coercivity of 45.7 Oe after annealing at 600°C. Because of these electrical, optical, and magnetic properties, Mn-doped thin films are promising for use in spintronic devices. [ABSTRACT FROM AUTHOR]

Abstract. The high-amplitude shock waves induced by the interaction of pulsed high-power laser with aluminum alloy 2024-T62 make the 0.2% offset yield strength, the ultimate tensile strength, surface hardness, elastic modulus, and Possion ratio of specimens increase by 13.3%, 13.4%, 117.5%, 24%, and 12%, respectively. In addition, the high surface residual compressive stresses, dense dislocations, and finer grains are formed in the sub-surface of shocked area. The relations between these factors and the fatigue life of the specimens are investigated. [ABSTRACT FROM AUTHOR]

Low temperature phase transformation of alkoxide-derived titania was studied under an oxygen flow containing water vapor. The addition of hexylene glycol to the titanium alkoxide solution was effective in transforming rutile phase at low temperature (300°C). Hexylene glycol seems to form a bidentate ligand structure with TEOT in solution state. This bidentate structure promoted the rutile phase at low temperature, under O2-steam treatment. This modification of TiO2 gel structure could be monitored by FT-IR and XANES. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the use of binary decision diagrams to represent general matrices. We demonstrate that binary decision diagrams are an efficient representation for every special-case matrix in common use, notably sparse matrices. In particular, we demonstrate that for any matrix, the BDD representation can be no larger than the corresponding sparse-matrix representation. Further, the BDD representation is often smaller than any other conventional special-case representation: for the n×n Walsh matrix, for example, the BDD representation is of size O(log n). No other special-case representation in common use represents this matrix in space less than O(n2). We describe termwise, row, column, block, and diagonal selection over these matrices, standard an Strassen matrix multiplication, and LU factorization. We demonstrate that the complexity of each of these operations over the BDD representation is no greater than that over any standard representation. Further, we demonstrate that complete pivoting is no more difficult over these matrices than partial pivoting. Finally, we consider an example, the Walsh Spectrum of a Boolean function. [ABSTRACT FROM AUTHOR]