Stability of 10B4C thin films under neutron radiation

• Published in: Radiation physics and chemistry (Oxford, England : 1993) Vol. 113; pp. 14 - 19
• Main Authors: Höglund, Carina, Zeitelhack, Karl, Kudejova, Petra, Jensen, Jens, Greczynski, Grzegorz, Lu, Jun, Hultman, Lars, Birch, Jens, Hall-Wilton, Richard
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-08-2015
• Subjects: 10B4C; Neutron; Neutron detection; Radiation damage; Thin film; 10B4C; Neutron; Radiation damage; Thin film; Neutron detection
• ISSN: 0969-806X; 1879-0895
• DOI: 10.1016/j.radphyschem.2015.04.006

Thin films of 10B4C have shown to be very suitable as neutron-converting material in the next generation of neutron detectors, replacing the previous predominantly used 3He. In this contribution we show under realistic conditions that 10B4C films are not damaged by the neutron irradiation and interactions, which they will be exposed to under many years in a neutron detector. 1μm thick 10B4C thin films were deposited onto Al or Si substrates using dc magnetron sputtering. As-deposited films were exposed to a cold neutron beam with fluences of up to 1.1×1014cm−2 and a mean wavelength of 6.9Å. Both irradiated and as-deposited reference samples were characterized with time-of-flight elastic recoil detection analysis, scanning electron microscopy, transmission electron microscopy, X-ray photoemission spectroscopy, and X-ray diffraction. We show that only 1.8ppm of the 10B atoms were consumed and that the film composition does not change by the neutron interaction within the measurement accuracy. The irradiation does not deteriorate the film adhesion and there is no indication that it results in increased residual stress values of the as-deposited films of 0.095GPa. From what is visible with the naked eye and down to atomic level studies, no change from the irradiation could be found using the above-mentioned characterization techniques.
•10B4C films are not damaged by radiation during many years in a neutron detector.•1μm 10B4C thin films were exposed to a 1.1×1014cm−2 cold neutron beam.•Only 1.8ppm of the 10B atoms were consumed.•No change in film composition, adhesion or residual stress.•10B4C based neutron detectors are very suitable replacements for 3He detectors.