© EnSol AS 2018
LaNNDe (Lanthanide based, solid-state Nanocomposite Neutron Detector technology)
Neutrons constitute a powerful tool for a wide range of scientific, medical and homeland security applications. They are uncharged particles with the ability to deeply penetrate into matter in a non-destructive interaction. Only a few isotopes of some elements can react to incident neutrons releasing one or more charged particles which can subsequently be amplified and detected as an electronic signal or ‘count’. The most commonly neutron absorbers are boron-10 (10B), lithium-6 (6Li) and helium-3 (3He), the latter being in most widespread usage around the world. However, the 3He shortage (2008)[1] makes urgent the development of a new neutron detector technology. Solid state neutron detectors are a cost effective and compact technology, and constitute an alternative to 3He gas detectors.[2] Most studied solid-state neutron detectors consist on thin film neutron reactive materials deposited under semiconductor diodes.[3] On the other hand, advances in nanotechnology now bring the possibility of coupling heterogeneous materials into single solid-state devices.[4] It is thus possible to develop a binary neutron detector system on the nanoscale – the neutron absorption process is isolated to a material in nanoparticle form and the electron conduction / charge separation to another encapsulating host / matrix material. EnSol has unique experience and equipment for the Physical Vapor Deposition (PVD)[5] of nanocomposite materials and devices. Our detector concept is based on utilizing lanthanide nanoparticles within a solid state device and incorporating signal processing electronics. By placing the neutron-absorbing nuclei (lanthanide nanoparticles, with gigantic absorption cross section values) inside the detector volume, rather than on the surface, a large efficiency in a small layer can be expected. [1] A. Cho, “Helium-3 Shortage Could Put Freeze on Low-Temperature Research”. Science, 326, 778-779 (2009). [2] A. N. Caruso, “The physics of solid-state neutron detector materials and geometries”. J. Physics. Condens. Matter, 22, 443201 (2010). [3] D. S. McGregor, R. T. Klann, J. D. Sanders, J. T. Lindsay, K. J. Linden, H. K. Gersch, P. M. De Lurgio, C. L. Fink, and E. Ariesanti, “Recent results from thin-film-coated semiconductor neutron detectors”. Int. Symp. Opt. Sci. Technol., 4784, 164-182 (2003). [4] P. M. Ajayan, L. S. Schadler, and P. V. Braun, “Nanocomposite Science and Technology”. (2006). [5] U. Helmersson, M. Lattemann, J. Bohlmark, A. P. Ehiasarian, and J. T. Gudmundsson, “Ionized physical vapor deposition (IPVD): A review of technology and applications”. Thin Solid Films, 513, 1-24 (2006).
