Edge-on detectors with active edge for X-ray photon counting imaging

摘要

The paper describes fabrication and testing of X-ray silicon edge-on detectors with active edge. In the edge-on strip detector configuration the photons are impinging on the chip edge and is absorbed parallel to the strip. The longer absorption length results in much higher quantum efficiency than face-on detectors (front-lluminated). To extend the sensitivity to ≤ 5keV the guard ring at one edge is replaced by an active edge made by 3D-processing. Test results with 241Am and 57Co sources are presented. Also it is shown that increasing the thickness to 2mm increases the efficiency at 122keV due to increased contribution from Compton events.