Characteristics of the stacked microstructured solid state neutron detector

High-efficiency microstructured semiconductor neutron detectors for direct 3He replacement

“…Furthermore, stacking two common thinfilm devices will not double the detection efficiency over a single device, a consequence of reaction product self-absorption. However, offset-stacking two MSNDs can double the detection efficiency, primarily due to the elimination of the neutron streaming paths in the semiconductor sidewalls [17][18][19]. MSNDs can be mass produced using inexpensive silicon VLSI processing techniques and readilyavailable 6 LiF neutron conversion material, among other conversion materials.…”

Microstructured semiconductor neutron detector (MSND)-based Helium-3 Replacement technology

“…However, recent advances with high-aspect ratio deep etching (HARDE) techniques, along with common MEMS wet-etching techniques, have allowed for unique microstructured neutron detector structures to be realized. Under such a configuration, the diode is etched with perforations which are backfilled with neutron reactive materials, such as 10 B or 6 LiF. As a result, the intrinsic thermal-neutron detection efficiencies of microstructured diodes have experimentally been shown to exceed 30%, representing a six-fold increase in neutron detection efficiency over their thin-film-coated counterparts [3][4][5].…”

“…The basic configuration consists of a common Schottky barrier or pn junction diode, upon which a neutron reactive coating, such as 10 B or 6 LiF, has been applied. The coated diodes are restricted to low thermal neutron detection efficiencies, typically no greater than 4.5% intrinsic efficiency in the case of 6 LiF, which is a preferred absorber material due to the large energy of the reaction products and the chemical inertness of the material [1,2]. The advantages of coated diodes as neutron detectors include compact size, a low power requirement, low cost VLSI production processes, and ruggedness.…”

Nevada National Security Site-Directed Research and Development FY 2011 Annual Report

“…In the past, semiconductor neutron detectors based on a planar diode configuration with a thin-film coating of a converter material (such as enriched boron [ 10 B], lithium [ 6 Li], or gadolinium [Gd]) were used. More recently silicon (Si) diode devices etched with perforated microstructures that are filled with converter material have been studied and found to be more efficient than the simple planar diode configurations (Conway 2009, Bellinger 2010, Nikolić 2010. In this study, the concept of a similar type of detector based on a porous Si matrix loaded with a fissile material, 235 U, was explored.…”