Temperature Dependence of the Behaviour of a Single-Sided Irradiated Silicon Detector

We have studied the behaviour of a single-sided, 50 micron pitch, AC-coupled, poly-resistor biased silicon detector, processed at CSEM ( Neuchatel, Switzerland) after having been irradiated with a fluence of 10^13 neutrons/cm2 . The irradiation has been performed simulating the CMS silicon tracker data taking environment, with the detectors under bias and the temperature at 0 C. During the july 1996 test beam period we tested the detector at different temperatures ( -10,-5,0,+5,+20 C) as a function of the bias voltage up to 200 V, with the 120 GeV pion beam of X7 area at CERN. On these conditions we measured a S/N ratio of 12-14, efficiency of 98-99 % and a spatial resolution of 11-13 micron.