Technical University of Denmark – Page 2

Reversible and irreversible temperature-induced changes in exchange-biased planar Hall effect bridge (PHEB) magnetic field sensors

Rizzi G., Lundtoft N.C., Østerberg F.W., Hansen M.F., Technical University of Denmark, DK

We generally investigate the use of exchange-biased planar Hall effect bridge (PHEB) magnetic field sensors for biodetection, where the sensors detect the binding and unbinding of magnetic beads to the sensor surface by biomolecular interactions. [...]

Injection molded superhydrophobic surfaces

Søgaard E., Smistrup K., Taboryski R., Technical University of Denmark, DK

The Lotus effect is used as inspiration for the fabrication of injection molded (IM) hierarchical polymer surfaces with self-cleaning properties. IM is a widespread method for the fabrication of plastic items. Surface functionalization is traditionally [...]

Increased Piezoresistive Effect in Crystalline and Polycrystalline Si Nanowires

Reck K., Richter J., Hansen O., Thomsen E.V., Technical University of Denmark, DK

This paper presents measurements of the size and doping dependence of the piezoresistive effect in top-down fabricated p-type crystalline and polycrystalline silicon nanowires. Test chips with 6 differently sized piezoresistors and integrated contacts for electrical [...]

Capillary filling speed in silicon dioxide nano-channels

Jarlgaard S.E., Mikkelsen M.B.L., Skafte-Pedersen P., Bruus H., Kristensen A., Technical University of Denmark, DK

We present a simple silicon-based fabrication technique for nanocapillaries based on controlled growth of silicon-dioxide, UV lithography, etching with etch-stop, and glass wafer bonding. Our approach improves state-of-the-art with respect to the obtained cross-wafer homogeneity [...]

Applications of Topology Optimization in the Design of Micro- and Nanofluidic Systems

Okkels F., Olesen L.H., Bruus H., Technical University of Denmark, DK

The material distribution method in topology optimization was developed in the late 1980ies for stiffness design of mechanical structures, and only recently the first steps have been taken towards implementing the method in fluidics. Topology [...]

TranSIESTA: A SPICE for Molecular Electronics

Stokbro K., Taylor J., Brandbyge M., Ordejon P., Technical University of Denmark, DK

With our newly developed method,TranSIESTA[1], it has become possible to model complex molecular electronics devices under operation conditions. In this presentation I will describe the basic principles behind the method and applications of the method [...]

Quasi-static Motion of Bubbles in Microchannel Contractions

Jensen M.J., Goranovic G., Bruus H., Technical University of Denmark, DK

We present a thorough theoretical and computational study of bubble dynamics in icrofluidic channels with contractions. We investigate the effects of geometry and surface physics (friction and contact angle) on the behavior of incompressible bubbles, [...]

Electroosmotic Pumping of Nonconducting Liquids by Viscous Drag from a Secondary Conducting Liquid

Brask A., Goranovic G., Bruus H., Technical University of Denmark, DK

A novel electroosmotic pump design relying on two-liquid viscous drag to pump nonconducting liquids is presented and analyzed theoretically. A conducting pumping liquid driven by electroosmotic flow (EOF) drags a nonconducting working liquid by viscous [...]

On Design of a Backplate Used in a Hearing Aid

Pedersen N.L., Technical University of Denmark, DK

In this work topology optimization is used to optimize the compliance or the eigenfrequencies of prestressed plates. The prestress is accounted for by including the force equivalent to the prestressing and adding the initial stress [...]

Systematic Design and Optimization of Multi-Material, Multi-Degree-of-Freedom Micro Actuators

Sigmund O., Technical University of Denmark, DK

The paper reports an automated method for the synthesis of multi-material, multi-degree-of-freedom micro actuators. The method is based on topology optimization, an iterative computational scheme consisting of alternating finite element analyses, sensitivity analyses and optimal [...]