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Single crystalline and textured In 2 O 3 thin films with (1 1 1) surface orientation, grown by plasma-assisted molecular beam epitaxy, were used as a model system to study the role of bulk and surface electron accumulation layer conductance for ozone sensing. Both conductance contributions, which add to the total film conductance, were systematically varied. The resulting ozone sensitivity was determined by total conductance measurements in synthetic air with defined ozone concentration using UV irradiation instead of heating to regenerate the In 2 O 3 surface. Depletion of the surface electron accumulation by an oxygen plasma treatment, confirmed by X-ray photoelectron spectroscopy, rendered the films ozone insensitive. The ozone response of films with an accumulation layer was increased by thickness reduction or by designing the bulk of the film semi-insulating using deep acceptor doping by Mg. Our results of using electron accumulation layers for gas sensing and bulk doping by deep acceptors to increase sensitivity can be generalized to other gas sensing materials. The use of single crystalline films allows selecting the most sensitive crystallographic surface orientation and may have further advantages over polycrystalline films, such as increased stability and sensing speed. [ABSTRACT FROM AUTHOR]

By the local electroreflectance method the topographic analysis of Ge1-x Six monocrystal surface was performed. The influence of the surface orientation on defects density distribution was found. Topographic maps of the defectiveness distribution on the crystal surfaces with (111) and (110) orientations were constructed and visualized. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations of nanoindentation are used to study the deformation behaviors of single crystal Zr for four different surface orientations. The comparison of results for two different potentials, an embedded atom method potential and a charged optimized many body potential, reveals the influence of stable and unstable stacking fault energy on dislocation behaviors under nanoindentation. The load–displacement curve, hardness and deformation behaviors of the various surface orientations Zr are compared and the elastic and plastic deformation behaviors are analyzed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Aluminizing treatment decreased the creep strength of superalloy. [•] Long-term exposure deteriorated the creep strength of coated superalloy. [•] Surface orientation affected the creep lifetime of coated superalloy. [•] Fracture deformation mechanism in coated superalloy was discussed. [Copyright &y& Elsevier]

Topologicalcrystalline insulators (TCIs) are a new class of topologicalmaterials that possess unique metallic surface states protected bycrystalline mirror symmetry. Their topological surface propertiesare expected to strongly depend on the surface orientation. By combiningdensity functional theory (DFT) calculations and synthesis experiments,we demonstrate the controlled growth of single crystalline nanostructuresof the prototypical TCI SnTe with distinct facets and morphologies.Our calculations suggest that the excess energy of the {111} surfacescan be either higher or lower than that of the {100} surfaces, dependingon the stoichiometry, while the {110} is always higher than the {100}.In our synthesis experiment, we qualitatively controlled the stoichiometryby tailoring the growth temperature and obtained two types of singlecrystalline nanowires: smooth nanowires dominated by {100} facetsat high temperatures and zigzag nanowires composed of both {100} and{111} surfaces at low temperatures. Notably, there is no {110} facetin our nanostructures, strongly supporting the DFT calculations. Ourdevice fabrication and electrical characterizations suggest that bothtypes of nanowires are suitable for transport studies of topologicalsurface states. [ABSTRACT FROM AUTHOR]