A 450 um-thick, fully depleted, backside illuminated, 1-Megapixel pnCCD detector with a 1024 * 1024-pixel format (pixel size: 75 * 75 um^2) has been installed and commissioned for imaging and spectroscopy applications at the Small Quantum Systems (SQS) instrument of the European X-ray Free Electron Laser (Eu.XFEL) facility .
The SQS instrument is operating at an energy range of 0.5 – 3 keV. However, the detector can handle photon energy of 0.3 – 25 keV with quantum efficiency of 80% or higher for 0.7 <= Eg <= 12 keV. This detector enables single photon imaging due to its very low noise of 3e– (highest gain) and can also detect up to 1500 photons per pixel (lowest gain). Our detector offers three operation modes with different bias voltages and 7 gains per mode. The mode of operation could be chosen per requirements for different experimental scenarios. Two of the operation modes have been calibrated using flat-field illumination of the detector and an aluminium target for fluorescence imaging at 1.5 keV.
Our pnCCD detector can also be used for spectroscopic measurements. We are currently analyzing data taken using Xe gas bombarded by 0.9 keV, 1.2 keV and 1.5 keV X-rays, and the results are promising.
My presentation focuses on a summary of the calibration and characterization of the pnCCD detector at Eu.XFEL.
 M. Kuster et al., J. Synchrotron Rad. 28 (2021), 576 – 587.