REAL-TIME MONITORING OF SINGLE-NEUTRON-INDUCED DAMAGE IN SILICON USING AVALANCHE PHOTODIODES OPERATING IN THE GEIGER MODE

Avalanche photodiodes in the Geiger mode have been used to monitor, in real time, the increase in dark-current generation rate caused by lattice damage induced by single fast-neutron elastic collisions. This damage has been monitored, at room temperature, for periods up to several days with a timing resolution as low as 10 ms. A variety of short-term and long-term annealing effects are observed as well as the creation of what appear to be multi-stable single-defect generation centers having switching times of several minutes. Although the observed short and long-term damage is consistent with that observed using a variety of other methods, our new technique has the sensitivity to permit the observation of the creation and evolution of individual multi-stable defects in relatively pure, very-low-defect concentration silicon which is depleted of mobile carriers so that many of the complicating effects of defect-impurity pairing and electron or hole trapping can be ignored.