Full text loading...
(a) Average resistance vs. strain curve of a 10 μm × 10 μm sized TMR sensor. The gauge factor calculated with Eq. (2) is 818. (b) The inset shows the rotation of the sensing layer magnetization (dotted arrow) against the reference layer one (solid arrow) where σ is the tensile stress and Hbias the applied magnetic bias field. (c) This inset displays a scheme of the experimental four-point-bending apparatus used for straining TMR sensors patterned on a Si specimen.
(a) A schematic of a self-sensing microcantilever based on magnetostrictive TMR sensors. Upward deflection causes tensile stress σ on the bottom side of the cantilever. This is detected by a resistance change of the deflection TMR sensor. The TMR sensor on the cantilever chip is not subjected to stress and can be used as a reference. (b) A scanning electron microscopy image (bottom view) of a self-sensing microcantilever including two TMR sensors on the cantilever and its chip.
Comparison of force vs. distance curves simultaneously measured with the TMR sensor (top) and the optical beam deflection system (bottom). The hysteresis between the approach and retraction curves for the TMR sensor is probably caused by magnetic hysteresis effects. The dashed line in the TMR curve represents a sensitivity of . The axis on top shows nominal strain acting on the TMR sensor.
Comparison of the AFM results obtained in tapping mode with beam deflection readout (left) and TMR sensor (right). On top are the resonance curves simultaneously measured by both readouts. The topography images of an optical grating are displayed at the bottom and were subsequently recorded at the same sample position using the conventional beam deflection and the TMR sensor signal as feedback, respectively. Line sections taken from the same positions are shown at the bottom of the two AFM images and reveal that the data quality obtained with both sensors is the same.
Article metrics loading...