Very High Temperature Hall Sensors in a Wafer-Scale 4H-SiC Technology

4H-SiC is a key enabler for realizing integrated electronics operating in harsh environments, which exhibit very high temperatures. Through advances in 4H-SiC process technology, different sensor and circuit types have been demonstrated to operate stable at temperatures as high as 800 °C, paving the way toward harsh-environment immune smart sensors. In this work, for the first time the operation of ion-implanted 4H-SiC Hall sensors realized in a wafer scale Bipolar-CMOS-DMOS technology is demonstrated at a wide operation temperature range spanning room temperature up to 500 °C in addition to short-term operation up to 600 °C. The temperature-dependent sensor characteristics of 15–22 samples are evaluated in terms of sensitivity and noise. The small inter-device variations reflect the stability of the used process for very high temperature Hall sensors. The noise-limited detectivity is further evaluated, revealing a best value of 950 nT/ (Formula presented.) and a mean detectivity of 1 µT/ (Formula presented.) at 500 °C. This is the best value reported up to date for very high temperature Hall sensors, besides being the first demonstration of ion-implanted wide-bandgap Hall sensors. Overall, the results reflect the potential of the demonstrated Hall sensors for the next generation of integrated magnetic field sensors in harsh environments.