Design and First Characterization of Active and Slim-Edge Planar Detectors for FEL Applications

This paper reports on the development of a dedicated technology for the fabrication of pixelated edgeless sensors to be used in X-ray imaging applications at free electron laser (FEL) facilities. The process was developed with the goal of producing planar sensors suitable for the tight FEL application requirements in terms of collection speed, spatial resolution, and radiation tolerance. At the same time, care has been taken to reduce the dead area at the borders of the sensors, thus minimizing the loss of information and distortion introduced when tiling several dies in a large area imager. Different active-edge and slim-edge terminations, designed with the aid of TCAD simulations, are discussed. Based on numerical simulations, a wafer layout was designed and devices with different configurations were fabricated. The experimental results from the electrical characterization of the produced p-on-n sensors and test structures are presented and discussed.