New surface morphology for low stress thin-film-coated thermal neutron detectors

Abstract

Experimental devices using patterns of holes etched into semiconductor surfaces are under evaluation for use as neutron detectors. The devices have miniature holes equidistantly spaced so as to completely cover the front surface of a planar semiconductor device. The devices have both electrical contacts and neutron-reactive coatings applied over the surface and within the holes. The tiny via holes assist in thin-film adhesion while offering a method to increase the thermal-neutron detection efficiency.

6:1 aspect ratio silicon pillar based thermal neutron detector filled with B10

“…This has led to the development of a variety of semiconductor based thermal neutron detectors. [1][2][3][4][5][6][7] Moving from a gas medium to a solid state material can dramatically reduce the size of the device by increasing the density of the neutron-absorbing material. An early approach for solid state thermal neutron detection is to coat a semiconductor material with the thermal neutron absorber/converter material.…”

Development of 10B2O3 processing for use as a neutron conversion material

“…These include boron-10-( 10 B) lined gaseous tubes, boron-10-triflouride ( 10 BF 3 ) -filled tubes, lithium-6-( 6 Li) doped scintillators, and other semiconductor based platforms utilizing 6 Li [1][2][3][4], 10 B or 10 B containing compounds [5][6][7][8][9][10] such as boron nitride, boron carbide [11] and boron phosphide. Our group has been developing a 3-dimenstional (3d) Si based "Pillar Detector," first reported in 2005 by Nikolic et al [8] with 10 B as the thermal neutron conversion material.…”

“…McGregor et al have developed a design based on 6 LiF in perforations, also a promising approach based on a 3d geometry. [1][2][3][4] Typically, thermal neutron detectors operate on similar principles, relying on an isotope with a high thermal neutron cross-section such as 3 He, 10 B, 6 Li,157 Gd and 113 Cd. An incident thermal neutron interacts with the neutron sensitive material, resulting in a nuclear reaction.…”

Nine element Si-based pillar structured thermal neutron detector

“…Several different designs of solid state thermal neutron detectors are currently being investigated [1][2][3][4][5]. Our design is based on a high aspect ratio PIN diode pillar arrays filled with 10 B which we have coined the "Pillar Detector" [6][7][8][9][10][11][12][13][14][15].…”