With the continual drive towards bigger, better, and brighter light sources, whole new areas of scientific research are possible that would have been unimaginable or even were believed impossible before. For example, imaging of single bioparticles has been demonstrated at Free Electron Lasers (FELs) [1], and synchrotron beamlines can now be used to study real-time changes in samples on a timescale of milliseconds. However, even the best experiment or the best light source is worthless if the employed detection system is not up to the task at hand. This is especially true for light sources like the current and upcoming generation of hard X-ray FELs, which introduce special challenges that are distinctly different from the challenges posed at current third-generation synchrotrons.
Cutting-edge area-detector developments currently are mostly, but not exclusively, based on the hybrid pixel design, where a pixelated sensor layer (typically silicon) is connected to a readout chip face-to-face by a fine array of solder bumps. The readout chip provides a separate readout channel for each pixel, allowing sophisticated parallel signal processing. This approach also makes it possible to optimize the sensor and the readout chip independently from each other, and profit from technological advances very quickly. Improvements in microchip production (Moore's law) make it possible to achieve faster readout, smarter signal processing, and smaller pixels, while new sensor materials and designs can have a range of benefits such as better quantum efficiency.
In the following, two hybrid pixel systems developed by the Photon Science Detector Group at DESY (FS-DS) are presented: The AGIPD system, for use at the European XFEL; and the LAMBDA system, which is currently being commissioned at PETRA-III synchrotron beamlines.