Time Resolution of the Mupix8, a large HV-MAPS prototype

The Mu3e experiment is searching for the charged lepton flavor violating (cLFV) decay $\mu \to$ eee with a planned sensitivity of 2 in 10${}^{15}$ decays for phase I. To achieve such a sensitivity, a fast, high resolution tracking detector is required which has a material budget of 0.1% per tracking layer to reduce multiple Coulomb scattering. A suitable technology for these requirements is the High Voltage Monolithic Active Pixel Sensor (HV-MAPS) concept. It combines fast charge collection via drift with a fully monolithic architecture of sensor and readout in one chip which can be thinned to 50 $\mu$m. The MuPix8 is the first large scale HV-MAPS prototype for Mu3e with a size of 1 $\times$ 2 cm${}^2$. It features circuitry to measure charge information which is used to correct for time walk. The time resolution of the system using time walk correction is presented.