Comparison of charge collection from energetic ions typical of neutron-recoil events with charge collection from alpha particle strikes

We describe experimental measurements of the charge collection from fluorine ions striking ICs. The fluorine ion strikes produce charge bursts similar to the charge bursts from energetic heavy ions produced when cosmic-ray-generated neutrons collide with silicon nuclei in an IC. Charge collection from the ions strikes is about ten times as large as from alpha strikes, too large to be easily overcome in DRAM design. The ion-beam technique provides a useful tool for investigating charge bursts of the silicon-recoil events, now thought to be a major source of DRAM errors.