Radiation hardness tests of highly irradiated full-3D sensors

Several full-3D silicon sensors (with column electrodes going fully through the bulk) were irradiated up to a fluence of (2.14±0.18)×10¹⁶ n_eq cm^-2. An infra-red laser was used to induce a homogeneous signal within each sensor's bulk. The signal degradation, measured as a signal efficiency (signal after irradiation normalised to its value before irradiation) was determined for each fluence. The experimental set-up allowed for monitoring of the beam spot diameter, position and reflection intensity on the sensor's surface. Corrections, dependent on the measured reflection intensity, were made when calculating the signal efficiency. The sensor irradiated to the highest fluence showed a signal efficiency of (50±5)%.