Radiation hardness of silicon diodes for high energy physics applications

Oxygenated and standard (not oxygenated) silicon diodes processed by CNM and IRST have been irradiated by 27 MeV protons and compared with standard devices from ST Microelectronics. As expected the leakage current density increase rate (α) and its annealing do not show any significant dependence on the starting material, oxygenation and/or processing of the considered devices. On the contrary, oxygenation improves the radiation hardness by decreasing the acceptor introduction rate (β) and mitigating the depletion voltage (V_dep) increase, with the β parameter depending also on starting material and/or effects related to device processing for standard diodes. Finally these results are included in a general review on the state of the art for silicon detector radiation hardening, confirming the good performance of the considered technologies.