Design, Fabrication, and Testing of a Modular Magnetic Field Microsensor on a Flexible Polymer Foil
In contrast to existing microelectromechanical systems (MEMS), this paper describes the development, fabrication, and testing of an anisotropic magnetoresistance (AMR) microsensor using a 7 μm thick polymer foil as substrate material. The modular magnetic field micro sensors are fabricated on a standard 4 in Si Wafer due to handling purposes during the sensor fabrication process. To enable a release of the micro sensors at the end of the fabrication process, initial investigations concentrated on the proof of principle applying a deep reactive-ion etching (DRIE) process to structure the Si wafer. The DRIE process was used to structure Si frames, which serve as carriers for the modular magnetic field micro sensors. For the evaluation of the fabricated modular magnetic field micro sensors, electrical resistance measurements were accomplished. The aim of these investigations was the characterization of the magnetic field dependence of the electrical resistance. The electrical output signal of the AMR sensors were subsequently compared to electrical resistance measurements of AMR sensors fabricated on a Si substrate and served as reference. The measurement results show a marginal effect of the substrate material on the characteristics of the AMR sensors.
Gentelligente Bauteile – Genetik und Intelligenz in der Produktionstechnik
Kurzfassung Werkstücke, die Informationen zu ihrer Fertigung gespeichert haben und sich ihren Weg durch die Produktion selbstständig suchen, oder Fahrwerkskomponenten, die ihren Zustand autonom überwachen und bei Bedarf selbstständig eine Inspektion veranlassen, mögen vielleicht noch wie Zukunftsvisionen klingen, werden aber im Sonderforschungsbereich 653 „Gentelligente Bauteile im Lebenszyklus – Nutzung vererbbarer, bauteilinhärenter Informationen in der Produktionstechnik“ bald Wirklichkeit.
Metallic Bead Detection by Using Eddy‐Current Probe with SV‐GMR Sensor
The progress of the ECT probe with micro magnetic sensor becomes possible to apply to various applications. The detection of micro metallic bead used for electric packaging has been reported in this paper. We proposed micro ECT probes with meander coil as exciter and spin‐valve giant magneto‐resistance (SV‐GMR) as receiver. Micro metallic bead(solder ball) with the diameter of 0.25 to 0.76 mm is used as a measuring object. We discuss the detection and alignment of metallic bead by using ECT technique.