Evaluation of ZnO(Ga) coatings as alpha particle transducers within a neutron generator

Abstract

We report investigations and preliminary results from efforts to develop a recoil alpha particle detector for use in a portable neutron generator. The associated particle sealed tube neutron generator (APSTNG) will be used as an interrogation source for the Nuclear Materials Identification System (NMIS). With the emission of 14.1 MeV neutrons produced by the D-T reaction, associated 3.5 MeV alpha particles are emitted. These neutrons and alphas may then be correlated in time and direction, thus effectively "tagging" the neutrons of interest for subsequent use as an active nuclear materials interrogation source. The alpha particle detector uses a ZnO(Ga) scintillator coating applied to a fiber optic face plate. Gallium-doped zinc oxide is a fast (1.5 ns decay time), inorganic scintillator with a high melting point (1975C) and an absolute light yield of 1.5% of NaI(Tl). The scintillator is coated with a thin layer of nickel in order to screen out light produced in the tube and scattered deuterons and tritons. This coating also serves to prevent the buildup of charge on the detector surface. Results to date indicate promise as an effective alpha particle detector for the APSTNG for future use in the NMIS.

An ultrafast X-ray scintillating detector made of ZnO(Ga)

“…Most of the research and applications used ZnO powders, ceramics, and thin polycrystalline patterns [15][16][17][18][19][20]. With the development of crystal growth technologies, doped ZnO crystal products can be purchased commercially [21,22], but they are not adequate for spectroscopy or imaging due to their extremely low scintillation efficiency. As ZnO decomposes near the melting temperature at ambient pressure, there are lots of efforts devoted for the single crystal growth of ZnO to avoid the decomposition [23,24].…”

The influence of target film material and coating on neutron yield and sputtering yield

“…In order to improve the high temperature resistance of deuterated polyethylene target, boron nitride, boron carbide, diamond and silicon carbide were used as protective layers. Compared with the previous coating materials [19,20], the above materials have lower energy loss. The above research is helpful to promote the research and development of high-yield neutron tube, and provides important reference for the research of target materials and protective layer materials.…”

Effect of Plasma Treatment on the Luminescent and Scintillation Properties of Thick ZnO Films Fabricated by Sputtering of a Hot Ceramic Target

“…Currently, there is a need for scintillation materials with improved temporal and performance characteristics. In this sense, zinc oxide (ZnO) is a promising material due to its high radiation resistance, high transparency to its own radiation, and a record fast decay kinetics (less than 1 ns) for near-band-edge luminescence (NBEL) [9][10][11][12][13][14]. The radiation kinetics of traditionally used scintillators is not single-component-as a rule, along with a fast component, there is a slow component, which leads to false alarms of the detector device.…”