SEU tolerance improvement in 22 nm UTBB FDSOI SRAM based on a simple 8T hardened cell

摘要

FDSOI technology has attracted considerable interests in space application due to its inherent high radiation resistance. An SEU hardened 8T SRAM cell is proposed and implemented in a test memory chip with advanced 22 nm UTBB FDSOI technology. Heavy ion experimental results show that the threshold LET of SEU for proposed 8T structure cell is up to similar to 24 MeV center dot cm(2)center dot mg(-1) and less dependences of upset on data pattern and test modes are observed. Moreover, multiple bit upsets are not appeared in bitmap analysis results even under effective LET values at similar to 129 MeV center dot cm(2)center dot mg(-1). The P-bb body biasing shows low influence on SEU rates in irradiation test, while the N-bb body biasing has ability to adjust the SEU sensitivity in a certain range. The error rate prediction indicates that this nanoscale FDSOI hardened SRAM is suitable for space application in harsh radiation environment.