Self-limitation of edge-generated currents in single-sided microstrip detectors after type inversion

Heavily irradiated p⁺-n single-sided microstrip detectors show no dramatic increase in the leakage current due to contributions originating from the cut region, despite, after type inversion, the space-charge region is touching the heavily-damaged, cutting edge, already at zero bias. In this paper, we present both theoretical and experimental results aimed at providing interpretation for such phenomenon. In particular, we show that, for high defect densities at the detector cutting edge, the hole density approaches locally its equilibrium value. Correspondingly, the net generation rate saturates, this ultimately limiting the amount of current which can originate from the detector edge. Measurements from devices irradiated at different fluences are in good agreement with simulation results