Abstract
A novel magnetotransistor using a separated drift field with a p+ ring around an emitter has been designed and fabricated. The operating principle of the proposed magnetic field sensor is based on the emitter injection modulation. The p+ ring around the n-type emitter confines drifted electrons in the emitter and hence, the induced Hall voltage in the emitter is increased. The measured relative sensitivity of the separated drift field magnetotransistor with the p+ ring is about 140 times larger than that of the device without the ring.