Abstract
We have studied the effects of irradiation induced damage on the detector response of a synthetic single crystal diamond radiation detector. Before introducing radiation damage, the spatial variation of the detector response was investigated using a highly focused 2.6 MeV proton beam. A very uniform response close to 100% charge collection efficiency (CCE) over the whole contact area was found at applied electric field strengths as low as 0.4 V μm–1. At lower biases, time dependent polarisation phenomena were observed and clearly reduced the average signal amplitude. Subsequently, the 2.6 MeV proton beam has been used to introduce radiation damage within selected areas. The ion beam induced charge imaging was repeated to probe the modified regions. Even at an applied electric field of 2.6 V μm–1, no signal above the analogue threshold of the system was observed in the areas which had received a dose larger then 5 × 1014 cm–2, whereas more than 90% CCE was reached in the area with 1012 protons cm–2. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)