Soft error rate comparison of 6T and 8T SRAM ICs using mono-energetic proton and neutron irradiation sources

We present experimental results of soft errors produced by proton and neutron irradiation of minimum-size six-transistors (6T) and eight-transistors (8T) bit-cells SRAM memories produced with 65 nm CMOS technology using an 18 MeV proton beam and a neutron beam of 4.3-8.5 MeV. All experiments have been carried out at the National Center of Accelerators (CNA) in Seville, Spain. Similar soft error rate levels have been observed for both cell designs despite the larger area occupied by the 8T cells, although the trend for multiple events has been higher in 6T.