Temperature-dependent characterizations of irradiated planar n+-in-n pixel assemblies

Measurements of the leakage current scaling and tuning of front-end electronics due to temperature changes in a range between −30 °C and 0 °C are presented. Assemblies have been irradiated to fluences of 6.8×1015neqcm−2. A leakage current temperature scaling parameter Eg,eff=(1.108±0.047)eV is found, which is compatible within errors to earlier measurements of non-irradiated or lower irradiated silicon. Secondly, sensitivity of tuning parameters of the employed front-end electronics in terms of threshold and ToT values can be seen. A study of current and charge collection efficiency in an assembly irradiated to a fluence of 2×1016neqcm−2 has been carried out, showing a current related damage factor αI compatible to studies at lower irradiation levels. Charge collection stays constant with consecutively applied annealing steps and front-end electronics shows only slight changes in tuning parameters.