Assessment of Displacement Damage Effects in 14-nm and 5-nm FinFET Technology Nodes

Abstract

This work assesses the displacement damage (DD) response of 14- and 5-nm bulk FinFET static random-access memories (SRAMs) and investigates the possibility of single-particle-induced displacement damage or "micro-DD" effects. The radiation response of advanced technology nodes is experimentally evaluated using observable circuit-level parameters, such as correctable bit flips, failed or stuck SRAM bits, dynamic operating current, and ring oscillator (RO) frequency. The usage of SRAM arrays allowed for statistically significant observations due to the large array size and sensitivity to transistor-level changes. Heavy-ion irradiations are used to study DD effects. Simulations are used to estimate the contributions of ionizing and non-ionizing effects occurring at the transistor layer after heavy-ion irradiations. 10-keV X-ray experiments are used to decouple total ionizing dose (TID) and DD effects. A Monte-Carlo simulation method using Stopping and Range of Ions in Matter (SRIM) simulations is presented to correlate the level of physical damage (size and number of defects) with bit cell failure (stuck bits) and support predictive simulations. The model was able to account for both micro-DD and cumulative-DD failure modes to bridge the gap between molecular-level defects and circuit-level failures. These results demonstrate the importance of micro-DD as a permanent failure mechanism, especially as circuit failures due to DD may become increasingly probable with continued scaling advancements.