Multiple Event Transient Induced by Nuclear Reactions in CMOS Logic Cells

This paper presents a methodology for analyzing the behavior of nanometer technologies regarding "multiple event transients" (MET) caused by nuclear reaction induced by atmospheric neutrons. For the first time, currents collected by several sensitive areas of an ASIC cell resulting from a nuclear reaction are addressed by simulation. Libraries of several thousand types of currents are obtained for neutron energy range between 1 and 200 MeV. Group of currents are simultaneously injected at SPICE level and their effects are monitored on the cell output. Following an amplitude criterion, output transient duration and associated occurrence probability are recorded. A 130 nm NAND gate from ATMEL Corporation is first used to illustrate the methodology and a comparison between single event transients and multiple event transients effects is presented Finally, results regarding five different combinational cells in the ATMEL 130 nm library are presented and discussed.