PROTON IRRADIATION ON AC-COUPLED SILICON MICROSTRIP DETECTORS

To test the radiation tolerance of full-size detectors, four large-are a AC-coupled single-sided silicon microstrip detectors were fabricated . The detectors had a size of 6 cm x 3.4 cm and were made out of a 300 mu m thick, high-resistivity, n-type silicon, simulating the p-side o f the double-sided silicon microstrip detectors being developed. The A C coupling layer had either a single layer of SiO2 or double layers of SiO2 and Si3N4, in combination with tile surface passivation of SiO2 or Si3N4. The detectors were irradiated at room temperature by 500 MeV protons at TRIUMF to a fluence of 5.7 x 10(13) protons/cm(2), promptl y stored at 0 degrees C after irradiation, and periodically measured o ver the following year. The full depletion voltages showed a substanti al annealing and a gradual anti-annealing. The result was compared wit h the predictions of existing damage parameterization. Time variation of other characteristics, such as leakage current, interstrip; and cou pling capacitances, and strip-edge micro-discharges was also followed.