Papers – Page 2 – TechConnect Briefs

Electronic Transport in Molecular Devices from First Principles

Di Ventra M., Lang N.D., Pantelides S.T., Virginia Tech, US

We present an overview of recent work by the authors in first-principles calculations of electronic transport in molecules for which experimental results are available. We find that the shape of the current-voltage characteristics is mostly [...]

Computer Program Simulation of Protein Structure I

Lu K.U., California State University, US

Quantum Mechanics is probabilistic, and cannot provide the precise structures of atoms. The Deterministic Theory of Atomic Structure consists of a set of Electrodynamic Equations. Their mathematical solutions provides definite stable orbits for electrons to [...]

Ab Initio Molecular Dynamics Study of the Pressure Induced Phase Transformations in Cristobalite

Klug D.D., Rousseau R., Uehara K., Bernasconi M., Tse J.S., National Research Council of Canada, CA

The mechanism for the pressure induced transformation of cristobalite to stishovite and post-stishovite phases has been obtained from constant pressure ab initio molecular dynamics simulations. The cristobalite to stishovite transformation is found to be a [...]

Phase Stability and Thermoelectric Properties of Alkali-Metal Doped Group IV Clathrate Compounds

Rousseau R., Toderov E., Uehara K., Tse J.S., National Research Council of Canada, CA

The relationship between phase stability and structure of alkali metal doped clathrate compounds of C, Si and Ge is investigated by a combination of first principles band structure calculations and qualitative tight binding theory. The [...]

Simulation of Two-level Tunneling States and Floppy Modes in Silica Glass

Trachenko K., Dove M.T., Heine V., University of Cambridge, UK

We present the results of a computational study of the low-energy dynamics of silica glass. Molecular dynamics simulation results show that parts of the glass structure can undergo large cooperative reorientations of SiO4 tetrahedra. These [...]

Thermodynamic Processes of Si-interstitial Clusters

Kim J., Birner S., Richie D.A., Wilkins J.W., Voter A.F., Ohio State University, US

Interstitial defects control the dopant diffusion in ion-implanted silicon by providing traps for and sources of mobile interstitials. A study of the energetics and structural properties of interstitial clusters1 elucidates their growth path: interstitial clusters [...]

Ab Initio Modeling of Boron Clustering in Silicon

Windl W., Liu X-Y., Masquelier M.P., Motorola, US

We present results of ab initio calculations for the structure and energetic of boron-interstitial clusters in Si and a respective continuum model for the nucleation, growth, and dissolution of such clusters. The structure of the [...]

Boron Diffusion and Activation in Silicon in the Presence of Other Species

Li H-J., Kohli P., Ganguly S., Kirichenko T.A., Zeitzoff P., Torres K., Banerjee S., Univ. of Texas Austin, US

Modeling and experimental investigation of B equilibrium diffusivity and its activation in Si in the presence of other species, including ab initio calculations, are presented here. The results suggest that incorporating other species along with [...]

Theoretical Investigations of Diffusion and Clustering in Semiconductors

Uberuaga B.P., Henkelman G., Jonsson H., Dunham S.T., Windl W., Los Alamos National Lab, US

Density functional theory studies of two systems have been conducted: mechanisms of self-diffusion in Ge and clustering of B in Si. In the case of self-diffusion of Ge, we find for the vacancy mechanism within [...]

Atomistic Modeling of Arsenic Diffusion and Activation

Dunham S., Fastenko P., Qin Z., Henkelman G., University of Washington, US

Understanding the diffusion and activation of arsenic is critical for the formation of low resistance ultra-shallow junctions as required for nanoscale MOS devices. In this work, we combine the results of ab-initio calculations with continuum [...]