Enhancement of magnetoresistance by geometric and intrinsic factors

Abstract

Two kinds of mechanisms for magnetic field sensors are discussed, namely, intrinsic and geometric magnetoresistance (IMR and GeMR). Two extreme cases are experimentally obtained in InAs and HgCdTe, respectively, and the results are in good agreement with numerical analysis by the finite difference method (FDM). By adjusting the aspect ratio of rectangular samples, we show that the magnetoresistance (MR) can be enhanced several times. It is also found that MR becomes almost independent of geometric factors in the strong IMR case. These results can be applied to optimize semiconductor magnetic sensor devices. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.