X-ray silicon detectors for measuring hard X-ray radiation damage effects

摘要

For high sensitivity hard X-ray detector applications there is a solid-state alternative using high purity, silicon as starling material. The paper presents some original results concerning a radiation hardened technology, to be used for obtaining X-ray silicon detectors and the behaviour of the special designed devices in a specific radiation environment. Original processing sequences were experimentally tested and results concerning the most performant technology suited for this specific application are presented. Specially designed gettering steps were applied by backside ion implantation and annealing for enhancing the minority carriers lifetime in the substrate material and for reducing leakage currents at orders less than 10 nA. After a complete presentation of the specific characteristics of the as obtained detectors, they were exposed and completely characterized in X-ray ambient up to dose levels of 108 md (E>50 keV). Solutions for increasing the detector sensitivity and stability in radiation environments are proposed.