A new explanation for some open questions of hadron irradiated silicon detectors

Abstract

In future high-energy physics experiments on silicon detectors will be widely used in extremely intense hadronic radiation. These high radiation levels will cause significant bulk damage, which leads to degradation of macroscopic properties of silicon detectors. Although several models have been presented to predict effective doping concentration (Neff) and leakage current in hadron irradiated silicon detectors, only inter-center charge transfer mechanism with non-Shockley-Read-Hall (SRH) statistics is satisfactory. From previous works it is evident that electron and hole cross-sections of defects that can participate in inter-center charge transfer have important effects on electrical parameters and especially Neff, but for most defects there are no data or only one of these cross-sections is known and usually at points much lower than room temperature. To model the hadron irradiated silicon detectors we used the extrapolated room temperature cross-sections of different levels of (V2) defect to estimate the important cross-sections of E70, E170 and inter-level cross-sections from leakage current data before and after annealing. This method, which is a more realistic model to estimate Neff, can be used to explain “proton–neutron puzzle” more precisely and gives useful information about the clustered defects that are responsible for reverse annealing in hadron irradiated silicon detectors. In addition, in this paper it was tried to present a qualitative explanation for “saturation of reverse annealing” in proton irradiated oxygenated silicon detectors, which can be the key for manufacturing more radiation-hard silicon detectors in the future.