Understanding the Competitive Interaction in Leakage Mechanisms for Effective Row Hammer Mitigation in Sub-20 nm DRAM

In this letter, we demonstrate the competitive interaction between different row hammer (rh) leakage mechanisms in sub-20 nm DRAM and its implications for process optimization. Using 3D TCAD simulation, the leakage induced by electron migration (EM) and capacitive crosstalk (CC) can be separately analyzed, revealing their competitive role in WL etching depth (ED). When both mechanisms coexist, an optimal WL ED that most effectively suppresses the rh effect is observed. The optimal value, depending on the relative contribution of each leakage mechanism, varies with failure threshold and crosstalk noise voltage amplitude. The results highlight the importance of understanding and assessing the competitive interaction between different rh leakage mechanisms for effective rh mitigation.