SHORT-TERM ANNEALING IN 14-MEV NEUTRON-IRRADIATED SILICON

Using pulsed sources of 14-MeV neutrons (dose ∼109 neutrons/cm2) and fission neutrons, an investigation of short-term annealing in silicon has been performed. In n-type material, for approximately equal amounts of stable damage, the amount of unstable damage at 5×10 -2 sec was ∼3.0 times greater for 14 MeV than for fission-neutron irradiation. Considering that the ratio of stable damage for equal neutron fluences is ∼2.8, the total and unstable damage ratios at this same time, for equal neutron fluences, are ∼4.6 and ∼8.5. Although the available dose of 14-MeV neutrons was small, it produced about a factor-of-two change in the carrier lifetime of high quality bulk material. No differences in the annealing curves were observed for fission-neutron irradiations varying by two orders-of-magnitude in dose, suggesting that the data obtained for 14-MeV neutrons would also be valid at higher doses. © 1969 The American Institute of Physics.