The effect of bias conditions on AlGaN/GaN 2DEG Hall plates

Abstract

This paper describes the operation of AlGaN/GaN two-dimensional electron gas (2DEG) Hall plates under various supply conditions (0.026 V to 1.27 V). The 100-µm-diameter octagon-shaped devices were microfabricated using metal-organic chemical vapor deposition of AlGaN/GaN on <111> silicon wafers and traditional photolithography techniques. Upon device characterization at various Hall supply voltages, we observed an increase in the residual offset from 0.1 mT to 1.4 mT (from 9% of measured signal to over 60% in a 1 mT magnetic field). In addition, the sensitivity (scaled with bias voltage) was constant at 76 ± 2.5 mV/V/T (stable within 3%) with high linearity (R2 > 0.99) across the tested operating conditions. This work demonstrates improved understanding of AlGaN/GaN sensor elements that may be monolithically integrated with power electronics, as well function within extreme environments.