Advantages of Integrated InSb Hall Sensors with a GaAs HBT Signal Processing Circuit

摘要

Monolithically integrating indium antimonide (InSb) magnetic sensors with heterojunction bipolar transistor (HBT) signal conditioning circuits enables magnetic sensor designs with improved levels of performance. As a first step, the HBT epitaxy is deposited on gallium arsenide (GaAs) substrates. Subsequently, the InSb sensor material is deposited into etched wells. The resultant InSb sensor element(s) and HBT circuit are processed together. Compared to silicon (Si) Hall sensors, integrated compound semiconductor sensors provide; higher sensitivity, improved S/N ratio, greater robustness against ESD (using incorporated Zener diodes), no switching noise, and clean signals since signal processing is analog and not chopped.