The high luminosity upgrade of the Large Hadron Collider, foreseen for 2026, requires the replacement of the ATLAS Inner Detector with a new all-silicon Inner Tracker (ITk). After an integrated luminosity of 4000 fb−1 the ITk Strip Detector will have been exposed to a large radiation fluence, corresponding to a 1 MeV neutron equivalent fluence of up to Φeq = 1.6×1015 cm−2, and an ionising dose of = 66 Mrad, including the safety factor of 1.5. A radiation hard n+-in-p micro-strip sensor for the use in the ITk has been developed by the ATLAS ITk Strip Sensor collaboration and produced by Hamamatsu Photonics. In this talk, the results obtained from the electrical characterization of the latest barrel ATLAS17LS sensor prototype before and after irradiation will be shown.
Surface properties of the barrel long strip full-sized and miniature sensors have been studied before and after proton, neutron and gamma irradiation up to the maximal fluences and radiation doses specified for ITk Strip Tracker. Sensors have been irradiated by protons at CYRIC, Tohoku University (Japan) and at CERN IRRAD proton irradiation facility, by neutrons from Ljubljana TRIGA reactor (Slovenia) and by gamma rays from 60Co source in UJP Praha (Czech Republic).
It has been verified, that the surface radiation damage does not influence the sensor stability. The breakdown voltage is well above the maximum operational voltage. All the tested surface parameters, such as the interstrip resistance and capacitance, coupling capacitance and bias resistance satisfy the ATLAS ITk specifications for strip sensors.
|Submission declaration||Original and unpublished|