US – Page 460 – TechConnect Briefs

Robust Algorithms for Boundary-Element Integrals on Curved Surfaces

Wang X., Newman J.N., White J.K., Massachusetts Institute of Technology, US

This paper presents a new approach to computing 1/r singularities on curved panels. By using carefully chosen mapping techniques, a curved panel with curved edges is mapped to a at panel with straight edges. Analytical [...]

3D Simulations of Ultra-Small MOSFETs: The Role of the Short Range Coulomb Interactions and Discrete Impurities on Device Terminal Characteristics

Gross W.J., Vasileska D., Ferry D.K., Intel Corporation, US

We have developed a three-dimensional particle based simulator with a coupled molecular dynamics routine that avoids the "double-counting" of the long-range portion of the Coulomb force. As opposed to drift-diffusion based simulators, the Monte Carlo [...]

Long-Range Coulomb Interactions in Small Silicon Devices: Transconductance and Mobility Degradation

Fischetti M.V., Laux S.E., IBM Research Division, US

In small silicon devices,conduction electrons in the channel are subject to long-range Coulomb interactions with electrons in the heavily-doped drain,source,and gate regions.We show that for devices with channel lengths shorter than about 40 nm and [...]

Hybrid CA/Monte Carlo Modeling of Charge Transport in Semiconductors

Saraniti M., Goodnick S.M., Wigger S.J., Arizona State University, US

We report on the modeling of ultra-small MOS devices using a newly developed full band device simulator. The simulation tool is based on a novel approach, featuring a hybrid Monte-Carlo/Cellular Automata simulation engine self-consistently coupled [...]

Electron Vortices in Semiconductor Devices

Mohseni K., Shakouri A., Ram R.J., California Institute of Technology, US

The hydrodynamic model of electron transport in semiconductors is analyzed and in analogy to uid mechanics the transport equation for the electron vorticity, rv, is derived. Aside from the classical hydrodynamic sources of vorticity, collision [...]

Ensemble Monte Carlo Simulation of Raman Scattering in an AlxGa1-xAs System to Determine the Relative Strength of the Polar Optical Modes

Shifren L., Ferry D.K., Arizona State University, US

A Monte Carlo simulation is used to study Raman scattering and the relative strengths of the polar optical modes in an AlxGa1-xAs system. The dual polar optical modes in the system are incorporated by including [...]

Self-Consistent Calculations of Spatial Electron Densities in Quantum Dots Using a Coupled Recursive Green’s Function and Poisson Solver

Badrieh F., Ferry D.K., Arizona State University, US

We are utilizing the Recursive Green's function method to calculate the conductance in quantum dots as a function of Fermi energy, magnetic field and random potentials. We have extended the use of the method to [...]

Modeling Artificial Molecules Composed of Coupled Quantum Dots

Akis R., Vasileska D., Arizona State University, US

Recently, there has been much interest in coupled quantum dots. With individual dots, if the energy levels can be resolved, then one can think of a dot as representing an "artificial atom" [1]. Thus, fabricating [...]

Hybrid P-Element and Trefftz Method for Capacitance Computation

Gyimesi M., Wang J-S., Ostergaard D.F., ANSYS, Inc., US

The paper discusses efficient electrostatic field solutions techniques to simulate micro electro mechanical systems (MEMS): adaptive p-elements to remove the burden of manual mesh refinement; hybrid finite elements - Trefftz formulation to treat open boundary [...]

Influence of Element Size on the Precision and Required Computational Effort for 3D FEM Interconnect Capacitance Simulations of ULSI DRAM Cells

Hieke A., Infineon Technologies Corporation, US

A fundamental proble of all FEM capacitance computations in MEMS and ULSI is to determine proper mesh size for the elements representing the considered model. In particular, opticaml mesh size selection is crucial for large [...]