Field Of Microsensors Research Articles

Study on the stress of micro-S-shaped folding cantilever

Micro-cantilever has shown wide application prospect in the field of micro-sensors, actuators, gyroscope, and so on. There are abundant research studies on simple cantilever beam models, but there are few on S-shaped folding cantilever with complex structure, although it is widely used. In order to study the deformation failure of S-shaped folding cantilever, the force analysis of S-shaped folding cantilever was carried out in this article, and the stress values of different positions under the external load of the cantilever were deduced. The finite element model about S-shaped folding cantilever was built based on software ANSYS. The theoretical calculation was compared with the finite element calculation, and the results showed that the max stress is 681 MPa based on the derived theoretical formula, the max stress is 673 MPa based on the ANSYS, the error is 1.18%, which can prove formula is accurate. To further validate the stress predicted by the mathematical modeling, a micro-force testing platform was built to test the cantilever. Since the stress value cannot be measured directly in the test, the force corresponding to the stress was taken as standard and compared it with the simulation. The tested external force was corresponding the yield limit. The results showed that the experimental force was 0.06462 N before the plastic deformation occurred, the theoretical outcome was 0.065231 N corresponding the yield limit, the error was 0.94%. Both simulation and experimental results depict that the theoretical model is effective for predicting the stress of the S-shaped folded cantilever. The theoretical model helps to enhance the efficiency, and improve the performance, predictability, and control of the S-shaped folding cantilever.

Advances in Magnetic Micro Thin-Film Transducers

Magnetic Micro Electro-mechanical Systems (Magnetic MEMS) provide transducer capabilities ranging from thin-film storage devices and micro sensors to micro actuator solutions. This paper provides an overview over magnetic thin-film devices developed at the Institute for Microtechnology at the Leibniz Universitaet Hannover`s Center for Production Technology (PZH) in Garbsen, Germany. In the area of data storage, it presents a microcoil for optical data storage. In the field of micro sensors it shows two inductive length measurement systems, an eddy current proximity sensor and a micro strain gauge for force measurements. Micro actuators built as linear positioners and as tilting platforms, as well as a new actuator principle based on the magnetic shape memory (MSM) effect conclude the paper.

The fabrication of porous coatings using laser spark atomisation

Abstract The laser spark atomiser (LSA) technique, LINA-SPARK™ is used to prepare porous coatings. It is shown that the crystalline phase of the target material is conserved after atomisation and film formation. Silicon forms oxide-free films under inert atmosphere (Ar), whereas it forms silicon oxide when adding 20% oxygen to Ar, and silicon nitride in pure nitrogen atmosphere. Films made out of calcium phosphate are deposited on titanium substrates. It is expected that their porosity will improve the prosthesis-bone reconstruction after chirurgical operation. Future application in the field of microsensors is also discussed. Finally, it is shown that running the LSA under low rate of particle formation, it is possible to deposit isolated Si particles onto Si substrate thus enabling microstructuration of the surface.

Electrochemistry and microsystems

Electrochemistry takes a key position in products and manufacturing processes of microtechnology, which has established a multi-billion dollar market with applications in information, entertainment, medical, automotive, telecom and many other technologies. In combination with microlithographic pattern generation electrochemical deposition processes are applied in manufacturing CDs and DVDs, nozzle plates for ink jet printers, read–write heads for hard magnetic disks and solder bumps for flip-chip technology. Three-dimensional microstructures with extremely high precision and aspect ratio are manufactured by means of LIGA technology, which combines deep lithography, electroforming and moulding process steps. Field assisted etching processes with ultra-short voltage pulses, anodization of silicon and field assisted ion exchange in glass have been successfully used for generating microstructures. Meanwhile, there are a huge number of microdevices, which utilize electrochemical phenomena. ISFETs and ion sensitive electrodes are standard components in the field of microsensors, microfuel cells will become high-performance power supply systems for mobile IT and entertainment products. In communication technology electrophoresis-based on electronic ink displays will become more and more important products. The most challenging development is dealing with so-called labs-on-a-chip which utilize electrochemical phenomena like electrophoresis, isoelectric focussing and electroosmosis to create a novel platform for ultra-miniaturized analytics in life sciences, medical diagnosis, environmental technologies and many other areas of modern development.

Chemical Microsensors

Rmecent developments in the field of chemical microsensors are leading to new applications for which these devices have the potential to supplement or replace traditional analytical chemical instrumentation. The fundamentals of current microelectronic, acoustic wave, optical fiber, and electrochemical microsensors are presented, and a few recent, exciting results in these areas are described. Although future opportunities in the microsensor field are numerous, many significant problems, the majority of them related to the materials utilized for the chemically sensitive layers that are the "front end" of these devices, remain to be explored and solved.