Testing and modelling neutron radiation damage in Silicon Photonics integrated circuits.

The foreseen upgrades for the Large Hadron Collider (LHC) and the CERN Experiments increase the radiation tolerance requirements for the optical readout of the Detectors. The High Luminosity upgrade of the LHC is set to improve integrated luminosity by tenfold compared to the original LHC design in the upcoming years. As a result, the quantity of particle collisions during a given period of time will considerably rise, leading to a significant increase in generated data. High-speed optical data transmission is used to transfer the data produced by the particle detectors to the data collection point. This work analyses the impact of neutron radiation on Silicon Photonics, which is a candidate technology for next generation of radiation tolerant transceivers for High Energy Physics (HEP) applications. The EP-ESE-BE Section at CERN is conducting an R&D project to develop radiation-resistant Photonic Integrated Circuits (PIC) for usage in the LHC detector harsh environment. The photonic integrated circuits engineered by our research team underwent extensive testing at unprecedented levels of neutron fluence. A maximum neutron fluence of 3.8·10^16 cm-2 was achieved, and the experimental results show small performance degradation after high neutron fluence irradiation. Several components were electro-optically measured during neutron irradiation, such as Ring Modulators, Mach-Zehnder Modulators, and silicon-germanium photodiodes. Further analysis of the effects induced by neutron irradiation on the photonic integrated circuits was conducted through TCAD simulations, which yielded good agreement with the experimental results.