The Belle II DEPFET pixel detector

The existing Japanese Flavour Factory (KEKB) is currently being upgraded and is foreseen to be comissioned by 2014. The new e super(+)e super(-) collider (SuperKEKB) will have an instantaneous luminosity of 8 x 10 super(35) cm super(-2) s super(-1), 40 times higher than the current world record set by KEKB. In order to handle the increased event rate and the higher background and provide high data quality, the Belle detector is upgraded to Belle II. The increased particle rate requires a new vertex pixel detector with high granularity. This silicon detector will be based on DEPFET technology and will consist of two layers of active pixel sensors. By integrating a field effect transistor into every pixel on top of a fully depleted bulk, the DEPFET technology combines detection and in-pixel amplification. This technology allows good signal to noise performance with a very low material budget.