31 research outputs found

    Area-Selective Low-Pressure Thermal Atomic Layer Deposition of Aluminum Nitride

    Get PDF
    This work demonstrates intrinsic area-selective deposition of AlN films by thermal atomic layer deposition (ALD). Using sequential pulses of trimethylaluminum and NH3 at a substrate temperature of 623 K, polycrystalline AlN was selectively formed on a thin layer of sputtered AlN that was patterned on thermal SiO2 grown on Si substrates. A pretreatment to remove native AlOxNy facilitated the selective growth of ALD-AlN. Transmission electron microscopy, X-ray photoelectron spectroscopy, spectroscopic ellipsometry, and atomic force microscopy examined the interfaces and layer thickness. As reported in this article, the deposition of AlN exhibits intrinsic selectivity, a trait that can be exploited to grow other III-nitrides selectively, such as GaN.</p

    Electrical characterization of hot-wire assisted atomic layer deposited Tungsten films

    Get PDF
    In this work, we applied conventional Van der Pauw and circular transmission line method (CTLM) test structures to determine the sheet and contact resistance of ultra-thin (1-10 nm) tungsten films grown by Hot Wire assisted Atomic Layer Deposition, as well as their temperature coefficient of resistance (TCR). We finally explored the field effect (FE) in these layers

    Probing Quantum Aspects of Gravity

    Full text link
    We emphasize that a specific aspect of quantum gravity is the absence of a super-selection rule that prevents a linear superposition of different gravitational charges. As an immediate consequence, we obtain a tiny, but observable, violation of the equivalence principle, provided, inertial and gravitational masses are not assumed to be operationally identical objects. In this framework, the cosmic gravitational environment affects local experiments. A range of terrestrial experiments, from neutron interferometry to neutrino oscillations, can serve as possible probes to study the emergent quantum aspects of gravity.Comment: Phys. Lett. B (in press). S. Sarkar's name was inadvertently missed from the list of authors for "Nature 393 (1998) 763-765." This has been now correcte

    Illusory Decoherence

    Full text link
    If a quantum experiment includes random processes, then the results of repeated measurements can appear consistent with irreversible decoherence even if the system's evolution prior to measurement was reversible and unitary. Two thought experiments are constructed as examples.Comment: 10 pages, 3 figure

    Strongly coupled chameleon fields: possible test with a neutron Lloyd's mirror interferometer

    Full text link
    The consideration is presented of possible neutron Lloyd's mirror interferometer experiment to search for strongly coupled chameleon fields. The chameleon scalar fields were proposed to explain the early and late time acceleration of expansion of the Universe. They may produce short-range interaction between particles and matter. This interaction causes phase shift of neutron waves in the interferometer. Estimates of sensitivity are performed.Comment: 11 p, 3 fig; the title is changed, extended feasibility consideration: expected intensity and systematic effect

    Gravitational Atom in Compactified Extra Dimensions

    Get PDF
    We consider quantum mechanical effects of the modified Newtonian potential in the presence of extra compactified dimensions. We develop a method to solve the resulting Schroedinger equation and determine the energy shifts caused by the Yukawa-type corrections of the potential. We comment on the possibility of detecting the modified gravitational bound state Energy spectrum by present day and future experiments.Comment: 12 pages, 2 figure
    corecore