Hexagonal Boron Nitride and Graphene Field Effect Transistor-based Neutron Detectors

Boron-based materials have been proposed as critical components for radiation dosimetry applications in space as well as for radiation shielding, specifically due to their ability to absorb thermal neutrons. Here, we report on developing radiation detector architecture based on hexagonal Boron Nitride (hBN) in conjunction with graphene field-effect transistors. To this end, single crystal growth of natural boron nitride (h^NaBN) and isotopically enriched boron nitride (h¹⁰BN, h¹¹BN) was done using Ni-Cr metal flux. To optimize the experimental parameters and device geometry, Monte Carlo simulations are performed using Monte Carlo N-Particles code (MCNP) and benchmarked with simulation results from GEANT4 code. Real-time resistance measurements are carried out upon irradiating device prototypes by a 2.5 MeV D-D neutron generator (Starfire nGen-800) with a neutron yield of 10¹⁰ neutrons/sec and neutron flux of 10⁶ neutrons/(cm².sec).