Error correction for transformed concave and convex MAGFETs with dc supply voltage

Abstract This study presents two curve-fitting models of concave and convex magnetic field-effect transistor (MAGFETs) with a dc bias voltage supplied at the gate of the MAGFET. Experimental results indicate that the highest absolute sensitivity S A , supply-current-related sensitivity S RI and supply-voltage-related sensitivity S RV are 1.39 V/T, 2004.8 V/AT and 0.46 V/VT for the concave MAGFET, and S A = 0.77 V/T, S RI = 512.4 V/AT, and S RV = 0.29 V/VT for the convex MAGFET with a 3 V dc supply voltage. A magnetic device with geometric parameters, L / W = 40 μm/40 μm and d = 2 μm, is the best choice to optimize sensitivity, but a MAGFET with geometric parameters, L / W = 40 μm/40 μm and d = 4 μm, is another good choice because of its consistent geometric correction factor. The proposed arrayed and symmetrical designs can increase output voltages and eliminate unwanted errors. Broadening the drain gap not only improves the linearity of the output voltage, but also clearly makes the error correction factor consistent for both concave and convex MAGFETs. Minimizing the aspect ratio reduces the sensitivity of the concave MAGFET faster than that of the convex MAGFET. In general, both concave and convex MAGFETs are suited to fabricating magnetic devices with a wide drain gap.

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