Radiation tolerance of a high quality synthetic single crystal chemical vapor deposition diamond detector irradiated by 14.8 MeV neutrons
ABSTRACT 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.
Full-textDOI: · 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       . This work has shown that energy resolutions for alpha particle interactions approach 0.6%   and 4% for 14.1 MeV neutrons through reaction number 8 in Table 1  . This table indicates all the neutron–carbon interactions that can take place in a center of mass energy range from 0–20 MeV. "
ABSTRACT: There have been many reports on charged particle and neutron production in LENR experiments but as of yet they have not been correlated in time with excess heat generation. Diamond sensors with palladium electrodes can be utilized to address this need. First results using a diamond sensor is presented.International Conference on Cold Fusion-17; 08/2012
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ABSTRACT: In this paper a novel on-line tritium monitor is presented. It is made with a single crystal diamond detector (SCD) covered with a thin layer of LiF 95% enriched in <sup>6</sup>Li. Thermal neutrons impinging on the LiF layer produce a and T ions which are detected by the active diamond. The pulse height spectrum shows two separated peaks due to a and T ions respectively. By a proper calibration in a reference thermal flux the number of <sup>6</sup>Li atoms and thus the absolute n+<sup>6</sup>Li → α+T reaction rate per unitary flux can be established. Once calibrated the detector can be used to measure the tritium production. Due to the many outstanding properties of diamond this detector could operate in the harsh working conditions of a fusion breeding blanket. A test of this detector was performed at the 14 MeV Frascati Neutron Generator (FNG). The detector was inserted inside a mock-up of the European Helium Cooled Lithium Lead (HCLL) Tritium Blanket Module (TBM), designed to validate the neutronic database for fusion application. The mock-up of the TBM was designed to perform a full set of experiments to validate tritium production code prediction comparing the experimental results with calculations. The measured tritium rate with the Li-Diamond detector are described in this paper. Comparison with calculations is in progress and will be reported in a future paper.Advancements in Nuclear Instrumentation Measurement Methods and their Applications (ANIMMA), 2009 First International Conference on; 07/2009
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ABSTRACT: A review of diamond-metal contacts is presented with reference to reported values of interfacial potential (Schottky) barriers and their dependence on macroscopic and microscopic properties of the diamond surface, the interface and the metal. No simple model can account for the overall spread of p-diamond barriers, although there are, for certain metals, correlations with metal electronegativity, interface chemistry and diamond surface preparation. Detailed studies are presented for a selected contact (Al-p-diamond) using real-time monitoring during metal growth from sub-nanometre to bulk films and subsequent in situ heating to 1000 °C. This contact, prepared in a clean vacuum environment on characterized single-crystal substrates, provides a case study for a combined in situ electrical and spectroscopic investigation using IV measurements for macroscopic diodes and real-time photoelectron spectroscopy for nanoscale metal films. Band bending during growth leads to a rectifying contact with a measured IV barrier height of 1.05 V and an ideality factor of 1.4. A transition from layered to clustered growth of the metal film is revealed in the real-time measurements and this is confirmed by AFM. For the annealed contact, a direct correlation is revealed by real-time photoemission between the onset of interfacial carbide formation and the change from a rectifying to an ohmic contact at 482 °C.Journal of Physics Condensed Matter 09/2009; 21(36):364223. DOI:10.1088/0953-8984/21/36/364223 · 2.35 Impact Factor