Study of Stuck Bit Error Mechanisms in Advanced Technology DDR4 SDRAMs

To investigate the single event effects and hard damage that advanced process commercial high-performance Dynamic Random Access Memory (DRAM) may experience in space environments, single-particle flip-flop thresholds and cross-section curves were obtained using picosecond pulsed lasers in an integrated manner. Stuck bit error irradiation experiments were conducted by irradiating protons and white light neutrons with varying energies. Comparisons with previous high-energy proton irradiation studies reveal that low-energy protons induce more significant stuck bit errors and noticeable annealing effects in this type of memory. The study also explores the influence of factors such as DRAM self-refresh interval and temperature on error characteristics. The formation mechanism of stuck bit errors is analyzed through comparative simulations using Technology Computer-Aided Design (TCAD), which confirms that these errors result from displacement damage rather than the microdose effect. Simulation results further indicate that the simultaneous introduction of cluster and point defects affects the transistor carrier activity, leading to an increase in device leakage current. This causes data loss before the refresh interval, ultimately resulting in stuck bit errors. Based on these findings, recommendations for protective measures are provided.