Sensitive magnetotransistor magnetic field sensor

Claim 1

A magnetic field sensor comprising a lateral bipolar magnetotransistor having in combination only one single emitter region, at least one collector region and a base region being low-doped with impurity atoms having at least one base contact heavily doped with impurity atoms, with said base region incorporated in the surface of a silicon substrate that is low-doped with impurity atoms and of reversed conduction type, the P/N junction between said base region and said substrate is reverse biased by means of at least one secondary collector contact provided in the surface of said silicon substrate and wherein said magnetotransistor's emitter region, collector regions and base contacts are adjacently aligned, said single emitter region being divided into two outer subregions adjoining a middle subregion free from interstices, all of which are mutually parallel and heavily doped and in which said middle subregion is of the same conduction type as said base region, while said two outer subregions are of the reversed conduction type.