Impact of Particle Radiation and Temperature on the Retention Time of DDR4 SDRAM Cells

In this study, four references of double data rate 4 synchronous dynamic random access memories (DDR4 SDRAMs) of different manufacturers and technology nodes are subjected to proton and heavy-ion irradiation at various energies and linear energy transfer (LET) values. This causes the emergence of low-retention time cells, also called weak bits (WBs). The WBs are characterized by varying the device under test (DUT) temperature and the average periodic refresh interval,
$t_{\mathrm {REFI}}$
. This characterization reveals that some WBs exhibit a variable retention time and that irradiation with heavy ions introduces much more variability in cell retention time than irradiation with protons. The data are discussed and compared with other results from the literature.