Contribution of GEANT4 to the determination of sensitive volumes in case of high-integrated RAMs

This paper deals with the use of short-range beams in order to measure the sensitive thickness of devices. In the case of a Hitachi 4-Mbit SRAM, /spl sigma/(E) measurements have been compared to GEANT 4 calculations, taking into account the effects of the overlayers. The analysis of the experimental data at two bias levels has pointed out that /spl sigma/(E) is directly correlated with the energy deposited in sensitive volume (SV) for low ranges, on the other hand charge collection mechanisms have a strong impact for long ranges.