FI – Page 3 – TechConnect Briefs

A Method for Solving Arbitrary MEMS Perforation Problems with Edge and Rare Gas Effects

Veijola T., Helsinki University of Technology, FI

We present an accurate and fast method solving arbitrary perforation problems utilizing a solver for an extended modified Reynolds equation, the Local Impedance Reynolds (LIR) solver. The extension includes an additional term in the Reynolds [...]

Pressure Sensor Elements Integrated with CMOS

Kiihamäki J., Vehmas T., Suni T., Häärä A., Ylimaula M., Ruohio J., VTT Information Technology, FI

We report the measurement and fabrication results of monolithically integrated capacitive pressure sensor elements. The device fabrication process is based on novel plug-up process, which enables monolithical integration of sensors and CMOS in a modular [...]

Supramolecular Self-assembly of Carbon Structures from Shungite Rock Using Only Water

Osipov E., Osipov S., Reznikov V., Osipov E., Osipov S., Shestakov Yu., Satakunta Polytechnic, Technology, Pori, Finland, FI

In spite the fact that fullerene and any type of carbon are not soluble in water the main goal of this work is to produce evidence of realization of a supramolecular self-assembly of carbon structures [...]

Improved Reproducibility in Porous Silica Sol-Gel Processing Using Tertiary Butanol Solvent

Rissanen A.K., Blomberg M., Kattelus H., VTT Technical Research Centre of Finland, FI

Silica aerogels and xerogels are porous materials, which possess many exceptional properties. The research for the use of aerogel thin films in MEMS applications, such as humidity sensors, biosensors and calorimetric devices, is still at [...]

Extending the Validity of Existing Squeezed-Film Damper Models with Elongations of Surface Dimensions

Veijola T., Pursula A., Helsinki University of Technology, FI

Border flow effects in squeezed-film dampers having a gap separation comparable with the surface dimensions are studied with 2D and 3D FEM simulations and with analytic models derived from the linearized Reynolds equation for small [...]

Model for Flow Resistance of a Rare Gas Accounting for Surface Roughness

Veijola T., Helsinki University of Technology, FI

The contribution of surface roughness is included in the flow resistance of rare gas flow channels. The statistical properties of the surface are taken into account in the model applying a novel approximation for the [...]

Hierarchical Finite Element Simulation of Perforated Plates with Arbitrary Hole Geometries

Råback P., Pursula A., Junttila V., Veijola T., CSC - Scientific Computing, FI

The squeezed-film-damping of micro-electro-mechanical devices may be reduced by creating a number of small holes into the structure. Unfortunately, in the simulation of the devices it is possible to consider only a few holes in [...]

Static Equivalent Circuit Model for a Capacitive MEMS RF Switch

Tinttunen T., Veijola T., Nieminen H., Ermolov V., Ryhanen T., Helsinki University of Technology, FI

A simulation model for static analysis of a doubly supported capacitive MEMS RF switch has been constructed using electrical equivalencies. Energy-conserving large-displacement macro models for beam deflection, gap capacitance, electrostatic force, and mechanical contact are [...]

End Effects of Rare Gas Flow in Short Channels and in Squeezed-Film Dampers

Veijola T., Helsinki University of Technology, FI

Simple approximate design formulas (+-5%) for calculating the elongation of the idealized viscous flow channel of rare gas at Knudsen numbers Kn < 100 due to the open end effects. Rectangular channels with a large [...]

Towards Color Sensitivity of Protein Based Artificial Retina

Lensu L., Frydrych M., Aschi C., Parkkinen J., Parkkinen S., Parkkinen J., Parkkinen S., Jaaskelainen T., Lappeenranta Univeristy of Technology, FI

Bacteriorhodopsin (BR) has been studied as a material for molecular electronics applications. Thin film elements based on BR and its variants in polyvinylalcohol (PVA) have been produced to determine the photoelectrical properties of the material [...]