Electron confinement in drift detectors by means of "channel-stop" implants: characterization at high signal charges

Electron confinement in the direction transverse to the drift can be implemented in silicon drift detectors by means of deep p-implants. The reduced broadening of the electron cloud due to the deep p-implants has been tested as a function of the signal amplitude up to 200000 electrons. The maximum number of electrons for which full confinement is achieved has been measured. The dependence of this threshold charge on the potential barrier generated by the deep p-implants, the size of the confinement, and the detector operating conditions are reported.