Signal charge sharing in multilinear drift detectors: design and experimental characterization

Multilinear silicon drift detectors (MLSDDs) are radiation detectors which combine excellent energy and position resolution with high count-rate capabilities. This is achieved by controlling the diffusion of the signal charges and limiting their lateral spread during the drift. This paper will present a study of the signal electrons' transport in MLSDDs in comparison with the experimental measurements. Three-dimensional simulations were carried out, taking into account diffusion effects and mutual electrostatic interaction between the signal electrons. A representative sample of these simulations will be presented. Signal sharing in a multilinear drift detector and in a "classical" multi-anode drift detector are characterized and discussed. The results are useful to tailor the design of MLSDDs for the detection of different kinds of radiation (e.g., optical photon, X-ray, ionizing particle) and to optimize signal charge sharing and detector performance according to a particular application purpose.