Speaker
Description
The European Synchrotron Radiation Facility (ESRF) is being subjected to the second phase of its upgrade. Thanks to this upgrade, the new storage ring will be able to deliver extremely brilliant and coherent X-ray beams, setting advanced requirements for the detection schemes used. Consequently, the detector development is aiming to an improved performance in terms of spatial resolution and detection efficiency.
In this regard, our group is active on the development of pixelated detectors using semiconductor sensors for photon counting. The existing silicon sensors are sufficient for soft X-ray experiments. To counterbalance limitations set to the detection efficiency as the X-ray energy increases and operate our detectors to energies in the range 30-100 keV, we investigate the use of semiconductor sensors made of high-Z materials.
Several prototype modules based on CZT, CdTe and GaAs sensors have been developed and tested in terms of imaging performance at the ESRF beamlines. Each module, consisting of a sensor bonded to a single Timepix chip, is coupled to the MAXIPIX readout system. I will report on the results obtained focusing on the comparison of the performance achieved among different sensors, including measurements of the modulation transfer function (MTF), the detective quantum efficiency (DQE) and the spatial homogeneity.
