Abstract :
A detailed simulation of silicon pixel detectors irradiated to the very high fluences, in the range (1015divide1016neqcm-2) foreseen for vertex detectors after the Large Hadron Collider luminosity upgrade, is presented. The charge collection properties and the detector response were computed for different silicon materials (Standard Float Zone, Diffusion Oxygenated Float Zone, Czochralski, epitaxial silicon), operating conditions (bias voltage, temperature) and detector geometries (sensor thickness, electrode size). At the maximum fluence (1016 neqcm-2) the signal is limited by charge trapping rather than by the thickness of the active volume. Since all the silicon materials studied so far have a similar trapping cross section, they are all expected to collect an average signal of 2000-2500 electrons at 600V bias voltage. A detection threshold of 1000-1200 electrons is required in order to have a 97% detection efficiency
Keywords :
electron detection; position sensitive particle detectors; radiation effects; readout electronics; silicon radiation detectors; Large Hadron Collider luminosity; charge collection properties; charge trapping; detector geometries; diffusion oxygenated float zone; electrode size; electron detection efficiency; epitaxial silicon; radiation hardness; readout electronics; silicon materials; standard float zone; ultra radiation-hard silicon pixel detectors; vertex detectors; Collision mitigation; Computational modeling; Electron traps; Energy loss; Large Hadron Collider; Neutrons; Radiation detectors; Silicon radiation detectors; Temperature sensors; Voltage; Charge collection; Large Hadron Collider (LHC); pixel; radiation hardness; silicon detectors;
