Proton Interactions in Microelectronic Systems Flown in the Low-Earth Orbits Typical of Space Station

Proton-induced spallation reactions result in the generation of intense microscopic concentrations of ionizations, mostly generated along the trajectory of the recoiling nuclear fragment. A variety of single event effects can be induced if sufficient charge is generated near sensitive microstructures. The single event upset is the best understood of these effects, and the dependence of the cross section for inducing upsets on incident proton energy can be explained by a simple microdosimetric model which assumes an upset occurs if and only if a threshold number of ionizations are generated within a sensitive volume. Accurate predictions of upset rates requires accurate estimates of the threshold number of ionizations and the dimensions of the sensitive volume.