Proton irradiation on AC-coupled silicon microstrip detectors

To test the radiation tolerance of full-size detectors, four large-area AC-coupled single-sided silicon microstrip detectors were fabricated. The detectors had a size of 6 cm/spl times/3.4 cm and were made out of a 300 /spl mu/m thick, high-resistivity, n-type silicon, simulating the p-side of the double-sided silicon microstrip detectors being developed. The AC coupling layer had either a single layer of SiO/sub 2/ or double layers of SiO/sub 2/ and Si/sub 3/N/sub 4/, in combination with the surface passivation of SiO/sub 2/ or Si/sub 3/N/sub 4/. The detectors were irradiated at room temperature by 500 MeV protons at TRIUMF to a fluence of 5.7/spl times/10/sup 13/ protons/cm/sup 2/, promptly stored at 0/spl deg/C after irradiation, and periodically measured over the following year. The full depletion voltages showed a substantial annealing and a gradual anti-annealing. The result was compared with the predictions of existing damage parameterization. Time variation of other characteristics, such as leakage current, interstrip and coupling capacitances, and strip-edge microdischarges was also followed. >