Development of neutron radiation damage model and comparison of the effects of neutron and proton irradiation on macroscopic properties of the silicon detectors

Silicon detectors are widely employed in the modern HEP experiments at particle colliders like LHC because of their excellent tracking and vertexing capabilities. However, the high irradiation levels of unprecedented luminosity of the HL-LHC physics programme of the CMS experiment, requires development of new generation of radiation hard silicon detectors. The radiation environment due to p-p collisions in HL-LHC would consist of both charged and uncharged particles (particularly protons and neutrons), which would reach fluence levels of about 1e16 n
_eq
cm
^-2
in tracker and endcap calorimeter regions. These high levels of incident fluence interact with the silicon detectors and cause radiation damage and hence affect the macroscopic properties of the detectors, viz. full depletion voltage (V
_FD
), leakage current (I
_LEAK
) and charge collection efficiency (CCE). In the present work, Technology Computer Aided Design (TCAD) simulation software - Silvaco, has been used to develop a radiation damage model for neutron irradiation. The effects of neutron and proton irradiation on macroscopic properties of the silicon detectors are also compared and presented in this work. For proton irradiation the already developed proton radiation damage model has been used. The simulation results related to those macroscopic properties are found to be in good agreement with the measurement results.