Radiation hardness study using SiPMs with single-cell readout.

A dedicated single-cell SiPM structure is designed and measured to investigate the radiation damage effects on the gain and turn-off voltage of SiPMs exposed to a reactor neutron fluence up to $\Phi$ = 5e13 cm$^{-2}$. The cell has a pitch of 15 $\mu$m. The fluence dependence of gain and turn-off voltage are reported. A reduction of the gain by 19% and an increase of $V_{off}$ by $\approx$0.5 V is observed after $\Phi$ = 5e13 cm$^{-2}$.