Lithium containing chalcogenide single crystals for neutron detection

Scintillation properties of semiconducting 6LiInSe2 crystals to ionizing radiation

“…In addition, these crystals often exhibit distinguishable variations in color and impurity content; previously published efforts have also demonstrated this common observation in LiInSe 2 samples [14][15][16]. Despite these difficulties, significant progress has been made concerning crystal growth and the understanding of the optical-electrical properties of this material for radiation detection [17][18][19].…”

“…LiInSe 2 has the ability to respond to ionizing radiation through direct charge carrier transport; however, charge carrier trapping is demonstrated in crystals affecting the overall charge collection efficiency [18,19]. In more recent years, radiation detection viability has been investigated with the incorporation of isotopically enriched lithium-6.…”

Neutron Imaging with Timepix Coupled Lithium Indium Diselenide

“…Initial research focused on synthesis of a single crystal, neutron sensitive material [11,12], to provide complementary capabilities to silicon or germanium based semiconductor photon detection systems. While experimenting with lithium containing chalcogenides, it was determined lithium indium diselenide exhibited neutron sensitivity while operating as a room-temperature semiconductor [13]. Furthermore, a direct neutron detection semiconductor offers a solution for a device exhibiting faster response time, gamma ray discrimination, improved detection efficiency and finer resolution.…”

“…While the competing reaction 115 In(n,γ) 116 In maintains a thermal neutron cross section of 202 b, the secondary gamma has a high escape probability and has not been observed to affect significantly the neutron signal [16]. To enhance the thermal neutron capture efficiency of the sensor material, the lithium used for crystal synthesis is isotopically enriched to 95% 6 Li [12,13]. When the incident neutron enters the bulk sensor material, it interacts via scattering or absorption as previously noted.…”

“…After dicing the boule, neutron sensitive regions of semiconductor grade crystal were selected to become LISe sensors [13]. To prepare the sensor for fabrication, the crystal was polished and etched in a 5% bromoethanol solution.…”