Optimization of a High-Temperature High-Pressure Direct Wafer Bonding Process for III-V Semiconductors
R. Martin, J. Kozak, K. Anglin, and W. Goodhue
University of Massachusetts Lowell
Many optoelectronic devices utilize a heterojunction of a pair semiconducting materials including high-efficiency MEMS devices, solar cells, LEDs, and VCSELs. One fabrication technique which achieves such a device is direct wafer fusion. To optimize the process, COMSOL Multiphysics 4.0 was used to test various geometric configurations of the fixture. 2D and 3D models were created in order ...
An Analysis of Spin-Diffusion Dominated Ferrofluid Spin-Up Flows in Uniform Rotating Magnetic Fields
S. Khushrushahi, A. Guerrero, C. Rinaldi, and M. Zahn
Massachusetts Institute of Technology, Cambridge, MA
Univeridad Industrial de Santander, Bucaramanga, Colombia
University of Puerto Rico, Mayaguez, Mayaguez, PR
This work analyzes the spin-diffusion dominated explanation for spin-up bulk flows in ferrofluid filled cylinders, with no free surface, subjected to a uniform rotating magnetic field. COMSOL results are compared to experimental results and analytical results. Simulating ferrofluid spin-up flows have many subtleties, especially when using a single domain region to model the ferrofluid cylinder ...
S. Loire, and P. Kauffmann
University of California
Santa Barbara, CA
Recently, electrokinetic flows have raised the interest of the scientific community. Driving flow with an electric field leads to promising applications for mixing, concentration, pumping application in lab on chips. However, current models are still inaccurate and don\'t fit the measures. The simple decoupled model developed by Ramos et al does not predict velocities for all parameters. ...
Modeling and Simulation of Artificial Core-Shell Based Nanodielectrics for Electrostatic Capacitors Applications
D. Musuwathi Ekanath, N. Badi, and A. Bensaoula
Center for Advanced Materials, University of Houston, Houston, TX
Dept. of Physics, University of Houston, Houston, TX
The need for high storage capacitors led to the development of polymer based capacitors. Polymers have high processability, mechanical flexibility, electrical breakdown strength and compatibility with printed circuit board (PCB) technologies; but usually have very low permittivity (K). In COMSOL Multiphysics software, the AC/DC module is selected and the In-plane electric currents are applied ...
P. Vincent, and P. Zevada
College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Oregon
Dept. of Tectonics and Geodynamics, Institute of Geophysics ASCR, v.v.i., Prague, Czech Republic
Extrusion of highly viscous lavas that spread laterally and form lava domes in craters of large volcanoes is associated with significant volcanic hazards. Gas overpressure driven fragmentation of the lava dome or collapse and slumping of marginal sections or entire mass of the dome can trigger dangerous pyroclastic flows that threaten surrounding populations up to tens of kilometers away. We ...
P. Mikulski, K. Mcilhany, and R. Malek-Madani
United States Naval Academy
Here we present and discuss numerical solutions to the paraxial wave equation using COMSOL (2D, PDE, General Form, time-dependent analysis). Ultimately, the goal is to extend this treatment of free-space beam propagation to the case of propagation through a medium that is non-uniform and subject to non-linear effects where the beam itself is modifying the properties of the medium in which it is ...
E. Javier, J. Alberto Bava, and G. Rodriguez
Facultad de Ingenieria Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina.
Facultad de Astronomia y Ciencias Geofisicas Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina.
This paper describes the development of a thermal model applied to a radiosonde system that calculates the average temperature on the printed circuit board PCB of the system. Using the thermal physics module called \"Conjugated Heat Transfer” of the COMSOL utility, simulations are performed which allow modeling the atmospheric conditions of the environment that the radiosonde will be ...
P. Krstic, and J. Park
Oak Ridge National Laboratory
Oak Ridge, TN
The gigantic magnitude features of the ionic current of electrolyte through carbon nanotubes (CNT) are explained by the dramatic increase of electroosmotic current induced by the strong slip at the CNT surface and the considerable excess volume charge inside the tube. In this study, we investigate the fundamental details of gating phenomena of such gigantic ionic current through CNT by using ...
H. Diaz-Alvarez, R. Costley, D. Whitlow, M. McKenna, C. Williamson, and O. Taylor
US Army Engineer & Development Center
Previous studies have determined that bridges radiate acoustic energy in the infrasonic frequency range. Initial interest in this topic was the result of trying to identify sources of infrasound recorded at stations deployed near bridges. A Finite Element model has been developed for a Pratt truss railroad bridge located at Ft. Leonard Wood, MO. The model consists of 3-D Euler beam elements ...
R. Tosh, and H. Chen-Mayer
Accurate metrology of radiotherapeutic absorbed dose to water requires assessing the radiation induced temperature change. The most direct method for doing this is water calorimetry, for which the established technique involves the use of slender thermistor probes that are sealed within a glass vessel containing high-purity water. The probes and vessel perturb the radiation field, via ...