Irradiation of thin diamond detectors and radiation hardness tests using MeV protons

Grilj, V.*; Skukan, N.*; Jaki, M.*; Kada, Wataru; Kamiya, Tomihiro

Two 50-m thick transmission type single ion detectors made of high purity scCVD diamond and of silicon, for each, have been partially (5050 m area) irradiated with 4.5-MeV proton microbeam at the Zagreb heavy ion microprobe facility, introducing almost homogeneous vacancy production over the whole device. IBIC measurement was performed during irradiation to monitor signal amplitude degradation as online and also to evaluate the ion fluence at the same time. Irradiation process was terminated when approximately 6% signal reduction was observed for each detector. The radiation damage of charge collection efficiency (CCE) of the scCVD diamond detector was further investigated using 2-MeV proton microbeam as an IBIC probe as well as the silicon SB detector using 1.3-MeV proton microbeam. CCE degradations in the both detectors for 4.5-MeV proton beam fluences are compared.