Radiation tolerance of a high quality synthetic single crystal chemical vapor deposition diamond detector irradiated by 14.8 MeV neutrons

Associazione EURATOM-ENEA sulla Fusione, Centro Ricerche Frascati, Via E. Fermi 45, I-00044 Frascati (Roma), Italy
Journal of Applied Physics (Impact Factor: 2.18). 10/2008; 104(5):054513 - 054513-6. DOI: 10.1063/1.2973668
Source: IEEE Xplore


Diamond exhibits many properties such as an outstanding radiation hardness and fast response time both important to design detectors working in extremely radioactive environments. Among the many applications these devices can be used for, there is the development of a fast and radiation hard neutron detector for the next generation of fusion reactors, such as the International Thermonuclear Experimental Reactor project, under construction at Cadarache in France. A technology to routinely produce electronic grade synthetic single crystal diamond detectors was recently developed by our group. One of such detectors, with an energy resolution of 0.9% as measured using an 241 A m α particle source, has been heavily irradiated with 14.8 MeV neutrons produced by the Frascati Neutron Generator. The modifications of its spectroscopic properties have been studied as a function of the neutron fluence up to 2.0×1014 n/ cm 2 . In the early stage of the irradiation procedure an improvement in the spectroscopic performance of the detector was observed. Subsequently the detection performance remains stable for all the given neutron fluence up to the final one thus assessing a remarkable radiation hardness of the device. The neutron damage in materials has been calculated and compared with the experimental results. This comparison is discussed within the nonionizing energy loss (NIEL) hypothesis, which states that performance degradation is proportional to NIEL.

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Available from: Marco Marinelli, Apr 26, 2014
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    • "There have been several reports on the interactions of charged particles or photons with diamond in recent history as the capabilities of synthetic diamond growth have allowed for electronic grade diamond to become available [8] [9] [10] [11] [12] [13] [14]. This work has shown that energy resolutions for alpha particle interactions approach 0.6% [13] [15] and 4% for 14.1 MeV neutrons through reaction number 8 in Table 1 [14] [16]. This table indicates all the neutron–carbon interactions that can take place in a center of mass energy range from 0–20 MeV. "
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