Minimization of charge sharing effect in silicon hybrid pixel X-ray detectors based on pattern recognition algorithm

Abstract

Hybrid pixel detectors are becoming a standard in modern fast X-ray imaging for material science, physics and medicine. However, charge sharing effect is the main limitation in increasing position resolution of these systems and also for using them for spectroscopy applications. In this paper we present novel algorithms which allow proper hit allocation even in the case of charge sharing and which can easily be implemented in an integrated circuit using submicron technology. In our simulation we take into account both the spread of the charge in the detector as well as the expected noise and mismatch in the readout electronics. The simulation was performed for the pixel size 80 μm × 80 μm, for the input referred noise ranged from 75 e- rms to 150 e- rms and the charge deposited in the detector from 1100 e- to 6600 e-, which are typical values for soft X-rays.