The PN-CCD detector for XMM and ABRIXAS

A 6 cm x 6 cm large monolythic charge coupled device has been developed and fabricated as focal plane X-ray detector for the European XMM satellite mission and the German ABRIXAS mission. This spectroscopic silicon detector is denominated pn-CCD because of its use of reverse biased pn-junctions as charge transfer registers, as ultra-thin homogeneous photon entrance window and far the on-chip electronics. Due to the pn-CCD concept, the whole wafer thickness of 300 mu m is sensitive to ionizing radiation. The read-out is performed in parallel and needs only 73 ms for the 36 cm(2) large detector area. A uniform low noise performance is realized by on-chip integrated JFET electronics. The two best pn-CCDs have been integrated in the flight cameras for XMM and ABRIXAS and extensively tested for the long term operation in space. The presentation comprises the basic concept of the detector, a short description of the flight device and its fabrication, tests and operation as well as the key performance parameters. The concluding outlook describes methods of further development of the pn-CCD.