Large surface X-ray pixel detector

A large surface semi-conductor photon counting pixel detector is being built. As a first step, this detector is optimized for X-ray crystallography. The aim is to provide a high dynamic range (>10/sup 9/), high counting rate (10/sup 7/ ph/s per pixel) and fast image readout (3 ms). A full custom chip has been produced and tested, and results will be presented. Prototypes of 6 cm/sup 2/ with pixels of 330 /spl mu/m /spl times/ 330 /spl mu/m have been built together with a full fast readout system. These prototypes have been tested in the D2am beam line at the ESRF synchrotron (Grenoble, France), for different photon energies (10 to 24 KeV). The signal is well out of the noise until 10 KeV. We give results on the efficiency as a function of the photon rate and the effect of the threshold on the efficiency between the pixels. Furthermore, to demonstrate the large dynamic range, we made diffraction images. We then describe the 6.4 cm /spl times/ 6.4 cm camera that we are building and our future plans.