Papers – Page 5 – TechConnect Briefs

The Level-Set Method for Modeling Epitaxial Growth

Ratsch C., Petersen M., Caflisch R.E., University of California, Los Angeles, US

A level-set model for the simulation of epitaxial growth is described. In this model, the motion of island boundaries of discrete atomic layers is determined by the time evolution of a continuous level-set funciton psi. [...]

Numerical Investigations of Laser Induced Crystallization and Stress Development in Phase Change Electroceramic Materials

Pirch N., Baldus O., Waser R., Kreutz E.W., RWTH Aachen, DE

Barium-Strontium-Titanate, BST, in the stoichiometry Ba0.7Sr0.3TiO3 to Ba0.5Sr0.5TiO3 is been considered as a promising candidate to enter into the DRAM manufacturing technology. The incompatibility between the temperatures required to crystallize the ferro/para-electric layer into the [...]

Molecular-Dynamics Study of Physical Properties in Sintered Nano-Particles

Kadau D., Kadau K., Lomdahl P.S., Entel P., Kadau D., Kadau K., Kreth M., Germann T.C., Holian B.L., Westerhoff F., Wolf D.E., Los Alamos National Laboratory, US

Nano-crystalline metals, in which the size of grains is in the nanometer range, exhibit physical properties different from ordinary polycrystalline materials, thus these materials are of technological interest [1]. One example is the increasing hardness [...]

The Electroreduction of Hydrogen on Pt(111)

Marzari N., Blum L., Car R., University of Puerto Rico, US

The electroreduction of hydrogen on Pt(111) in acidic media is the primary fuel cell reaction. The explicit mechanism for this process involves a first order phase transition, which is due to the rotation of the [...]

An Effective Model for Microscopic Intrinsic Localized Modes

Kalosakas G., Bishop A.R., Los Alamos National Laboratory, US

We present a system of coupled degrees of freedom that can effectively describe the localization of intra-molecular excitations in the charge transfer solid PtCl. These excitations correspond to the Raman active motion of chlorines (symmetric [...]

Three Dimensional Adhesion Model for Arbitrary Rough Surfaces

Deladi S., Krijnen G., Tas N.R., Elwenspoek M.C., University of TWente, NL

We present a 3D adhesion model based on the JKR theory applied locally for all contacting asperity couple and the calculations account the van der Waals interaction beside the externally applied force. Thus, equilibrium of [...]

First-principles Study of Electron Transport through Atomistic Metal-Oxide-Semiconductor Structures

Zhang X., Fonseca L.R.C., Demkov A.A., Motorola, Inc., US

We describe a theoretical scheme to combine first-principles molecular dynamics simulation and non-perturbative scattering theory for transport calculations. We compare our approach with published results for electron transport through a single Al atom. The method [...]

Molecular Control of the Drain Current in a Buried Channel MOSFET

Yang J., de la Garza L., Thornton T.J., Kozicki M., Gust D., Arizona State University, US

We present results from a buried channel MOSFET with a molecular monolayer deposited on the surface. After attachment of the monolayer, the threshold voltage of the device shifts by approximately – 4.5 V. We explain [...]

Effects of Structural Deformation and Tube Chirality on Electronic Conductance of Carbon Nanotubes

Svizhenko A., Maiti A., Anantram M.P., NASA Ames Research Center, US

A combination of large scale classical force-field (UFF), density functional theory (DFT) and tight-binding Green’s function transport calculations is used to study the electronic properties of carbon nanotubes under the twist, bending and AFM-tip deformation. [...]

Effects of Disorder in Reduced Dimensional and Quantum Electronics

Weaver B.D., Aifer E.H., Naval Research Laboratory, US

We discuss the effect of atomic disorder on electronic systems that operate in either reduced dimension or by quantum-mechanical transport. Systems include high electron mobility transistors, tunnel diodes, superconductors, multiquantum well infrared and ultraviolet detectors, [...]