The BLBC3-D NanoCompass from Baolab Microsystems S.L., Terrassa, Spain, is a pure CMOS MEMS sensor that uses Lorentz force sensors to detect the Earth's magnetic field in 3D. The MEMS structure, which is a moveable aluminum plate suspended by springs, is constructed using the metal interconnect layers of the CMOS chip by etching away the inter-metal dielectric using vapor HF. When a current passes through the plate, it experiences a force proportional to the surrounding Earth's magnetic field and the resulting displacement is measured using capacitive detection between the moveable plate and fixed electrodes around it. The device provides 5° heading resolution and 13 bits per axis.
Baolab Microsystems S.L.