Magnetotransistor in CMOS technology

An investigation of the magnetic-field sensitivity of a lateral double-base contact n-p-n magnetotransistor compatible with CMOS technology is reported. An approximate theoretical analysis of the sensitivity is made. Two physical mechanisms are considered: current deflection and injection modulation. The deflection mechanism is more significant. It yields a sensitivity proportional either to the Hall mobility of the minority carriers if the accelerating field is weak, or to the sum of the Hall mobilities of both carrier types if tile field is strong. The sensitivity is also proportional to the base length. Experimental results corroborate the theoretical predictions. Relative sensitivities of the collector current as high as 1.5 µA/µA . T are measured.