In questa sezione troverete i lavori presentati alle Conferenze mondiali COMSOL. Le presentazioni descrivono ricerche e prodotti innovativi progettati con COMSOL Multiphysics da colleghi di tutto il mondo. I temi delle ricerche presentate abbracciano un'ampia gamma di settori produttivi e aree applicative, in ambito elettrico, meccanico, fluidodinamico e chimico. Lo strumento di Ricerca Rapida vi permetterà di trovare le presentazioni che si riferiscono all'area di vostro interesse.

Finite Element Analysis of Contact Studies of Radio Frequency MEMs Switch Membranes

J. Liu [1], V. B. Chalivendra [1], C. Goldsmith [1], W. Huang [1]
[1] University of Massachusetts - Dartmouth, Dartmouth, MA, USA

Radio frequency (RF) micro-electro mechanical system (MEMS) switch works in on/off modes controlled by electrostatic forces. In off mode, rough surfaces of electrodes come into a contact. Membrane contact surfaces have complex surface roughness patterns and the mechanical contact problem is very challenging to understand. The capability to predict contact quality becomes extremely important to ...

Chip Drop After Silver Sintering Process

M.H. Poech[1], M. Weiß[1], and K. Gruber[1]

[1]Fraunhofer Institute for Silicon Technology, Itzehoe, Germany

Since a couple of years, sintering becomes more and more important for power electronics. To press a semiconductor under high temperature in silver paste on a substrate promises benefits for durability. Tests with semiconductors of different thickness expose some problems. After the cool down, some of them fall slightly from the substrate. Stress in the boundary layer, caused by different ...

DNA Interactions in Crowded Nanopores - new

K. Misiunas[1], N. Laohakunakorn[1], S. Ghosal[2], O. Otto[1], U. F. Keyser[1]
[1]University of Cambridge, Cambridge, UK
[2]Northwestern University, Evanston, IL, USA

The motion of DNA in crowded environments is a common theme in physics and biology. Examples include gel electrophoresis and the self-interaction of DNA within cells and viral capsids. Here we study the interaction of multiple DNA molecules within a nanopore by tethering the DNA to a bead held in a laser optical trap to produce a "molecular tug-of-war". We measure this tether force as a function ...

CFD-based Evaluation of Drag Force on a Sphere Unsteadily Moving Perpendicularly toward a Solid Surface: a Simple Model of a Biological Spring, Vorticella Convallaria

S. Ryu[1], and P. Matsudaira[2]
[1]Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
[2]Department of Biology and Bioengineering, Massachusetts Institute of Technology, Cambridge, MA, USA

Vorticella convallaria, a sessile peritrich ciliate having a contractile stalk, is regarded as a model biological spring because of its remarkably fast contraction. Because the cell body shrinks to sphere-like shape during contractions, it can be assumed to be a sphere moving in quiescent water, and Vorticella’s contraction force has been evaluated with Stokes’ law. In this study, we ...

Passive Microsensor Based on LC Resonators for Substance Identification

D.A. Sanz Becerra[1], E.A. Unigarro Calpa[1], J. Osma[1], F. Segura[1]
[1]Universidad de los Andes, Bogotá, Colombia

A scheme for inductive wireless powering and readout of passive LC sensor is presented. The sensor’s inductor is designed as a planar square coil and is used as the power receiving component. The capacitor is connected directly to the inductor and it was designed as an interdigital capacitor. With a transmitting coil (coupling antenna), an electromagnetic field is generated which couples with ...

Design and Optimization of Highly Sensitive Single Axis Accelerometer using COMSOL Multiphysics®

Kunal A.Kshirsagar[1], K.Govardhan[1],
[1]VIT University, Sensor System Technology, School of Electronics Engineering, Vellore, Tamil Nadu, India
[2]VIT University, MEMS & Sensor Division, School of Electronics Engineering, Vellore, Tamil Nadu, India

Accelerometers are successfully commercialized MEMS devices. COMSOL Multiphysics® has been used in the modeling, simulation and optimizing of this design. The piezoresistive accelerometer is made up of a square proof mass with flexures supporting it. The piezoresistors are placed near the proof mass and frame ends of the flexure and the springs. There is an elongation or shortening of the ...

Simulation of an AlN Thin Film Resonator for High Sensitivity Mass Sensors

M. Maitra [1], H. B. Nemade [1], S. Kundu [1],
[1] Indian Institute of Technology Guwahati, Guwahati, Assam, India

The objective of this paper is to show the simulation of a piezoelectric thin film device and its application as a sensor. Piezoelectric aluminum nitride thin film clamped at two ends is simulated using COMSOL Multiphysics software. The device consists of the piezoelectric thin film suspended on a cavity etched on a silicon substrate. Two metal electrodes are placed at the two fixed sides of the ...

Near-Field of Resonating Piezoelectric Membrane Used as Ultrasound Transducer

V. Tzanov [1], J. Munoz [1], F. Torres [1], N. Barniol [1],
[1] Universitat Autonoma de Barcelona, Bellaterra, Spain

Micro-machined ultrasound transducers have a wide range of applications. As a sensor or actuator they can be used for measuring fluid speed and direction, to mix and excite particles (sonication), for taking images (ultrasonography), for non-destructive testing and many other purposes in wide variety of fields. For this particular study, a simplified model of micro-machined piezoelectric ...

A Novel Free-standing Evanescent Waveguide for Sensing

X. Meng [1], Y. Xin [1], P. French [1],
[1] Department of Microelectronics, Delft University of Technology, Delft, Netherland

Introduction The monitoring of bacteria concentration in drain fluid is the most common way to estimate the success of a colon surgery. However, the lack of efficient method to follow the development of E.coli in drain fluid after surgery is often fatal to the patient. The proposed device can reduce the diagnostic time to a few minutes with a low cost solution. In this investigation, a MEMS ...

Green's Function Approach to Efficient 3D Electrostatics of Multi-Scale Problems

C. Roman [1], L. Schmid [1], L. Stolpmann [1], C. Hierold [1],
[1] ETH, Zurich, Switzerland

We present an efficient method to compute efficiently the general solution (Green's Function) of the Poisson Equation in 3D. The method proves its effectiveness when dealing with multi-scale problems in which lower dimensional objects, such as nanotubes or nanowires (1D), are embedded in 3D. Our case-study is a field effect device with a carbon nanotube channel having diameter around 2 nm and ...