Charge collection in X-ray pixel detectors based on SI-GaAs doped with Cr

An analysis of the performance of X-ray pixel detectors based on SI-GaAs doped with Cr has been carried out. An analytic form for electron and hole currents of a pixel has been obtained. The detector based on our material has high charge-collection efficiency only when the pixel contacts are anodes in contrast to LEC SI-GaAs. The mean charge collected on pixel contact is calculated for radiation energies of 30 and 60 keV (charge is averaged over all monoenergetic photons irradiating the detector cell).