Properties of HPK UFSD after neutron irradiation up to 6e15 n/cm2

Understand

In this paper we report results from a neutron irradiation campaign of Ultra-Fast Silicon Detectors (UFSD) with fluences of 1e14, 3e14, 6e14, 1e15, 3e15, 6e15 n/cm2.

• The UFSD used in this study are circular 50 micro-meter thick Low-Gain Avalanche Detectors (LGAD), with a 1.0 mm diameter active area.
• They have been produced by Hamamatsu Photonics (HPK), Japan, with pre-radiation internal gain in the range 10-100 depending on the bias voltage.
• The sensors were tested pre-irradiation and post-irradiation with minimum ionizing particle (MIPs) from a 90Sr based \b{eta}-source.