Mu3e is an upcoming experiment searching for charged lepton flavor violation in the rare decay mu->eee. In the Standard Model of particle physics the branching ratio for the decay mu->eee is suppressed to below 10E-54, but the branching ratio is enhanced to observable levels in many models for new physics. In order to suppress both accidental and irreducible physics background, a silicon pixel tracker in a 1T magnetic field will deliver precise vertex and momentum information and two timing systems will deliver sub-nanosecond timing information. Since the decay electrons have low momentum (<53 MeV/c), multiple Coulomb scattering dominates the resolution of the tracking detector and an ultralight detector design is required. The full integration of pixel sensor, analog and digital electronics into a 50um thick HV-MAPS chip allows for a tracking detector designs with a layer thickness of just 0.1% of a radiation length X0. In the recent years a series of HV-MAPS chip prototypes for Mu3e have been developed and tested both in the laboratory and at test beams successfully.
An overview of the technical concept of Mu3e and the recent results from detector R&D will be presented.