Ground-based thermal neutron reaction products (a, Li-7) appear to be an im
portant terrestrial SEE concern for modern submicron technologies. We addre
ss some interesting spatial and temporal characteristics of neutron product
s. Accurate modeling of the temporal behavior of these products may be requ
ired for high-speed devices. In addition, we introduce a simulation methodo
logy that determines device sensitivity to neutron reaction products as a f
unction of neutron nuclear reaction location and the resulting ion track or
ientation.