Timing resolution performance of Timepix4 bump-bonded assemblies

The timing performance of the Timepix4 application-specific integrated circuit (ASIC) bump-bonded to a 100\; thick n-on-p silicon sensor is presented. A picosecond pulsed infrared laser was used to generate electron-hole pairs in the silicon bulk in a repeatable fashion, controlling the amount, position and time of the stimulated charge signal. The timing resolution for a single pixel has been measured to 107\;ps r. m. s. for laser-stimulated signals in the silicon sensor bulk. Considering multi-pixel clusters, the measured timing resolution reached 33\;ps r. m. s. exploiting oversampling of the timing information over several pixels.