RF MEMS Research Group
Eindhoven, The Netherlands
In this paper it is shown how the equivalent circuit parameters of a MEMS resonator can be simply obtained from an eigenfrequency simulation. Additionally, it is demonstrated that the Q-factor as a result of support losses in a MEMS resonator can be determined using a matched boundary layer. The method is applied to calculate the frequency dependent admittance of a diamond disk resonator. Results ...
G. Vaivars, P. Ndungu, and V. Linkov
South African Institute of Advanced Material Chemistry, University of the Western Cape, Cape Town, South Africa
In a fuel cell-powered engine, the fuel is converted to electrical energy through electrochemical reactions instead of combustion. Long term stability is required for automobile and other energy system applications. The agglomeration of catalyst particles leads to an irreversible decrease of the electrochemical performance, and there are no viable methods to compensate for this phenomenon.Complex ...
F. Cacho, V. Fiori, C. Chappaz, C. Tavernier, and H. Jaouen
STMicroelectronics, Crolles, France
In advanced semiconductor devices, most of the reliability issues in interconnects occur at a local scale. More precisely, the voiding phenomenon in copper lines is one of the key issues. Hence, a better understanding of the mechanisms governing electromigration would enable the development of more accurate predictive models.A model of vacancy migration is proposed. The thermal, stress and ...
R. El Otmani1, M. Zinet1, M. Boutaous1, P. Chantrenne1, and H. Benhadid2
1CETHIL, Université Lyon, Villeurbanne, France
2Laboratoire de Mécanique des Fluides et d'Acoustique, Université Lyon, Ecully, France
During injection moulding of thermoplastic parts, high pressures, velocities and temperatures are experienced by the polymer in the filling phase. The numerical simulation of this phase is a complex task, especially for semi-crystalline polymers, because it involves a coupling between heat transfer, material structural transformation and crystallinity. The aim of this work is to present ...
Simulation of Hygro Swelling Induced Stresses in Flip Chip Interconnects in a Stress-Sensitive Chip-on-Board Configuration
Optics & Packaging, CSEM SA, Central Switzerland Center, Alpnach, Switzerland
Flip chip interconnections are used for the direct electrical connection of face-down electronic components like MEMS pressure sensors. The investigated bonding technologies are gold stud bumping in combination with anisotropic conductive adhesives (ACA) and solder ball bumping in combination with underfill in a chip-on-board configuration. The modeled chip is an absolute pressure sensor based on ...
On the Use of COMSOL Multiphysics to Understand and Optimize the Filling Phase in the Injection and Micro-Injection Molding Process
M. Moguedet1, P. Namy2, and Y. Béreaux3
1Pôle Européen de Plasturgie, Bellignat, France
2SIMTEC, Grenoble, France
3LAMCOS, Site de Plasturgie, INSA Lyon, Bellignat, France
The work presented here deals with the simulation of the cavity filling stage of the injection and micro-injection molding process for thermoplastic materials.COMSOL Multiphysics gives us the means to take into consideration some other aspects usually neglected in commercial 3D softwares dedicated to polymer processing. In particular, tracking of the flow front is based on a Level Set approach. ...
E. Baur, M. Sabathil, and N. Linder
Osram Opto Semiconductors GmbH, Regensburg, Germany
For a proper design shaping of light emitting diodes, the exact knowledge of the current distribution in the active area is essential. On the one hand, one has to achieve a uniform current density over the chip area, on the other hand, one has to avoid current crowding in the neighborhood of the electrical contacts. In this paper it is shown first how a LED can be modeled by COMSOL Multiphysics. ...
Study of Electronic Properties of Nanocrystals from Different Points of View: From a Simple 2D Electrostatic Approach to 3D Poisson-Schrödinger Simulations
D. Deleruyelle, A. Guiraud2, and G. Micolau2
1Université Provence (Aix-Marseille I), Marseille, France
2Université Paul Cézanne (Aix-Marseille III), Marseille, France
In this paper, a study of the electronic properties of nanocrystals is presented. During this work, COMSOL Multiphysics has been used to develop various approaches to study the evolution of the floating potential of a single nanocrystal embedded in a dielectric medium. First of all, we considered the nanocrystal as a perfect conductor and applied a simple 2D electrostatic treatment, using ...
G. Ovchinnikov1, and V. Ovchinnikov2
1Laboratory of Internal Combustion Engines, Vladimir State University, Vladimir, Russia
2Micro and Nanofabrication Centre, Helsinki University of Technology, Finland
Electronic fuel injectors, widely used for gasoline spark ignition engines, are characterized by the fact that the volumetric efficiency, response time and spray pattern drastically change due to build up of deposits in the fluid-flow channels. This study is intended to describe the effect of channel shape and needle valve lift on the characteristics of a fuel flow in the pintle-type injector ...
G. Cammarata, M. Iacono, L. Cammarata, and G. Petrone
Department of Industrial and Mechanical Engineering, University of Catania, Catania, Italy
In this study, fluid-dynamics and thermal performance of active-chilled beams are investigated through 2D and 3D modeling in COMSOL Multiphysics. Three different typologies of air conditioning systems are considered. Results, obtained for typical ranges of variation in operational conditions, are principally produced as temperature and velocity distributions.Special attention is paid to the ...