Investigation of Neutron Flux resolution and Efficiency of the Neutron Intercepting Silicon Chip (NISC)

Results from the Neutron Intercepting Silicon Chip’s (NISC) exposure to a thermal neutron beam are presented in this study. The NISC measures neutron flux by taking advantage of B10’s significant cross section (3840 barns) to (0.025eV) neutrons. The B10 interaction with neutrons produces the charged particles Li 3+ and He 2+. These charged particles are produced in the B10 enriched Borosilicate glass (BPSG) that is layered on top of each MOS transistor in the flash chip. This results in the charge particles passing through the memory cell and disrupting the charge in the capacitor. Commonly described as a soft error, these interactions can be qualified as a bit flipping from a “1” to a “0”, or the voltage of the bit’s capacitor decreasing. In interests of measuring the effectiveness of the NISC as a neutron detector, multiple detectors were exposed at UT Austin’s TRIGA MARK II nuclear reactor. The results show that the NISC has significant neutron beam resolution and efficiency over standard gold-foil techniques.