Optimization of the extraordinary magnetoresistance in semiconductor-metal hybrid structures for magnetic-field sensor applications

TL;DR

This paper models and analyzes the extraordinary magnetoresistance effect in semiconductor-metal hybrid structures, highlighting the impact of contact resistance on device performance for magnetic-field sensors.

Contribution

It introduces a finite element model incorporating contact resistance, providing insights into optimizing EMR in hybrid structures for sensor applications.

Findings

Contact resistance reduces EMR by 30% at room temperature.

Finite element model aligns well with experimental data.

Considering contact resistance is crucial for accurate EMR prediction.

Abstract

Semiconductor-metal hybrid structures can exhibit a very large geometrical magnetoresistance effect, the so-called extraordinary magnetoresistance (EMR) effect. In this paper, we analyze this effect by means of a model based on the finite element method and compare our results with experimental data. In particular, we investigate the important effect of the contact resistance $\rho_c$ between the semiconductor and the metal on the EMR effect. Introducing a realistic $\rho_c=3.5\times 10^{-7} \Omega{\rm cm}^2$ in our model we find that at room temperature this reduces the EMR by 30% if compared to an analysis where $\rho_c$ is not considered.