Proposal of a new magneto-transistor with a recombination region in the base of the bipolar transistor

A new type of magneto-transistor, which has a recombination region in the base region, is proposed and demonstrated to have potentially very large sensitivity as an all silicon magnetic sensor. The operational principle of the magneto-transistor is quite different from traditional ones. When injected carriers (electrons) from the emitter into the base are deflected toward the recombination region formed in the base by the application of a magnetic field, the collector current, Ic, is extremely reduced because of the reduction of the transport factor of the injected carriers. The Si magneto-transistor, with very small size, is formed on an SOI substrate. It has been demonstrated that this prototype Si magneto-transistor has a suitable bias-voltage condition for very high sensitivity, ΔIc/Ico, such as 500-1000% at 1 kOe, even though being noisy because of the very small collector current.