Electrical properties of the sensitive side in Si edgeless detectors

Silicon edgeless detectors represent a novel type of detector that are being developed for close-to-beam applications in high-energy physics and for large-scale tiled 1D and 2D arrays used in radiation imaging. In this work, the electric field and potential distributions on the device cut side, key factors in detector performance, have been investigated using two methods—the Conductive Microprobe Technique and the Scanning Transient Current Technique. It has been found that the behaviour of the potential distribution at the edge indicates a significant presence of positively charged states, with the charge density changing with the applied voltage. This work will predict, to a first approximation, the trend of the electric field at the edge of these devices after irradiation to high fluences. This prediction will provide key inputs in the development of edgeless radiation hard detectors.