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Electric compasses are gaining importance as an important sensor in Various consumer electronics products. New sensor solutions are still interesting if they can simultaneously provide sufficient resolution,high stability, low power consumption, small form factor, and a low cost. Taking this as the goal, we havedesigned and fabricated micromechanical magnetometers intended for a 3D electronic compass whichcould be embedded in portable devices. The sensors are based on the Lorentz force acting on a current-carrying coil, processed on a single crystal silicon resonator. Sensors for the three Cartesian components of the magnetic field Vector can be processed on the same chip. The Vibration amplitude is detected capacitively and the resonance is tracked by a phase-locked loop circuit. The fabrication process is basedon aligned direct bonding of a double side polished and a SOI wafer. Magnetometers measuring the fieldcomponent along the chip surface have a flux density resolution of about 10 nT/Hz at a coil current of 100 uA.Magnetometers measuring the field component perpendicular to the chip surface are currently less sensitive with flux density resolution of about 70 nT/Hz. Resolution is limited by the fundamental thermomechanical noise.