Self-powered micro-structured solid state neutron detector with very low leakage current and high efficiency

We report on the design, fabrication, and performance of solid-state neutron detector based on three-dimensional honeycomb-like silicon micro-structures. The fabricated detectors use boron filled deep holes with aspect ratio of over 12 and showed a very low leakage current density of similar to 7 x 10(-7) A/cm(2) at -1V for device sizes varying from 2 x 2 to 5 x 5 mm(2). A thermal neutron detection efficiency of 4.5% +/- 60.5% with discrimination setting of 500 keV and gamma to neutron sensitivity of (1.1 +/- 0.1) x 10(-5) for single layer was measured without external bias for these devices. Monte-Carlo simulation predicts a maximum efficiency of 45% for such devices filled with 95% enriched 10 boron. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729558]