Numerical analysis of magnetic-field-sensitive bipolar devices

Two-dimensional numerical solutions to the system of partial differential equations governing galvanomagnetic carrier transport in magnetic-field-sensitive integrated bipolar transistors are presented. The equations are discretized using the finite box procedure with a variation in the standard Scharfetter-Gummel approach adopted for the current continuity equations. High-resolution computations of the potentials in the base region of realistic device structures and operating conditions show that the magnitude of the Hall voltage at the emitter-base junction is too small to cause any appreciable asymmetric minority carrier injection thus invalidating the widely invoked emitter injection modulation model. Measured data obtained using in situ Hall probes are in support of the conclusions derived from the numerical model