Comparison of accelerated DRAM soft error rates measured at component and system level

Single event upsets from terrestrial cosmic rays (i.e. high-energy neutrons) are more important than alpha particle induced soft errors in modern DRAM devices. A high intensity broad spectrum neutron source from the Los Alamos Neutron Science Center (LANSCE) was used to characterize the nature of these upsets in DRAM technologies ranging from 180 nm down to 70 nm from several vendors at the DIMM component level using a portable memory tester. Another set of accelerated neutron beam tests were made with DRAM DIMMs mounted on motherboards. Soft errors were characterized using these two methods to determine the influence of neutron angle, frequency, data patterns and process technology. The purpose of this study is to analyze the effects of these differences on DRAM soft errors.