Anomalous angle dependence of the output signal of bipolar magnetic sensors

Abstract

An unknown to date anomalous output-signal angle dependence in bipolar silicon magnetic sensors in amperometric mode of operation at low temperatures is discovered and investigated experimentally. This finding is in contrast to the expected sinusoidal behaviour of the output signal. We offer an interpretation based on the nonlinear magnetodiode effect that generates an additional angle-dependent potential and increases the potential barriers of the two directly connected collectors. As a result, angle dependence of the p/sup +/-n junction resistances is observed that modulates the current between the collectors. The absence of the new effect after a certain value of the temperature T/sub 0/, T>T/sub 0/ is due to the decrease of carrier mobility leading to linearity of the galvanomagnetic process in the microsensor.