Sensitivity of the silicon high-resolution 3-dimensional magnetic-field vector sensor

An integrated silicon magnetic-field sensor is presented which is capable of simultaneously measuring all three components of the magnetic-field vector. Moreover, the spatial resolution of the measurements is high (8 ×10 × 20 µm) to, facilitate measurements of highly divergent three-dimensional magnetic fields. The sensor is based on a single n-p-n multicollector transistor and it is fabricated in standard bipolar IC technology. The lateral part of the collector current has been used to sense the component of the magnetic field perpendicular to the surface of the chip, while the vertical component of the current is responsible for the sensitivity to in-plane magnetic fields. The elements of the sensitivity matrix of the sensor are discussed along with their dependence on the bias conditions.