An induced annealing technique for SiPMs neutron radiation damage.

The use of Silicon Photo-Multipliers (SiPMs) has become popular in the design of High Energy Physics experimental apparatus with a growing interest for their application in detector area where a significant amount of non-ionising dose is delivered. For these devices, the main effect caused by the neutron flux is a linear increase of the leakage current.\\ In this paper, we present a technique that provides a partial recovery of the neutron damage on SiPMs by means of an Electrical Induced Annealing. Tests were performed, at the temperature of 20\textdegree{}C, on a sample of three SiPM arrays ($2\times3$) of 6 mm$^2$ cells with $50\ \rm \mu m$ pixel sizes: two from Hamamatsu~\cite{MPPCHAMAMATSU} and one from SensL~\cite{SENSLSIPM}. These SiPMs have been exposed to neutrons generated by the Elbe Positron Source facility (Dresden), up to a total fluence of $8 \times 10^{11}$ n$_{\rm 1 MeV-eq}$/cm$^2$~\cite{Cordelli:2017dgl}. Our techniques allowed to reduced the leakage current of a factor ranging between 15-20 depending on the overbias used and the SiPM vendor.