Radiation Response of Advanced Dynamic Random Access Memories (DRAMs)

The radiation response of ten types of NMOS dynamic RAMs (DRAMs) was studied in a total dose and prompt dose rate environment. The test ensemble represented a cross section of state-of-the-art advanced semiconductor memories presently available off the shelf from five vendors and included eight types of 64K DRAMs and two types of 16K DRAMs. Samples were drawn from fourteen different date codes covering a span of more than one year. The observed dose to failure level was generally higher than earlier DRAM memories but is still only comparable to the dose specified for systems with moderate requirements. Functional upset occurred within the typical range for upset of other semiconductor technologies. The relatively large dispersion in vendor-to-vendor hardness data points to the need for hardness assurance controls by the user.