Magnetic field sensors can be used to measure the position of machine parts and products without contact. However, conventional sensors usually only detect the field strength of the magnetic field perpendicular to the chip surface. This is often sufficient, but prone to interference and inaccurate. Dr. Markus Stahl-Offergeld, Dr. Hans-Peter Hohe and Michael Hackner (from left to right) from the Fraunhofer Institute for Integrated Circuits were not satisfied with this. They wanted an exact position measurement with the advantages of magnetic field sensors and developed a 3D Hall sensor. The scientists interconnected several sensors on a chip in order to increase the measuring accuracy of the individual sensors. They then arranged the sensors in such a way that they can measure the three-dimensional magnetic field in one point. The sensor chip has a separate sensor for each of the three magnetic axes. These are combined in a so-called pixel cell and, depending on the measurement speed, achieve a resolution of a few microtesla.