Neutron induced radiation damage of a n-type Ge detector influence of the operating temperature

The energy resolution of a n-type HPGe detector has been measured as function of the operating temperature before and after inducing radiation damage by neutrons from a fusion evaporation reaction. The aim of the investigation was to determine an appropriate operating temperature for Ge multidetector arrays. In the undamaged condition the leakage current due to thermal production of charge carriers limits the operating temperature to below 125 K. With neutron induced trapping levels the operating temperature has to be decreased to below 100 K because of thermal activation of trapping levels and defect migrations.