Spatially confined electric field effect for improved resistive switching behavior of a Ni/Ta-embedded TaOx/NiSi device

Abstract

In this study, Ni/TaOx/NiSi and Ni/TaOx/Ta/TaOx/NiSi devices were fabricated, and the resistive switching (RS) behaviors were investigated. A 2 nm-thick Ta metal layer was deposited between two TaOx films to form a Ni/TaOx/T/TaOx/NiSi stack, which was analyzed using TEM. Based on a linear scale I-V curve and an R-V graph, both devices showed conventional bipolar conductive bridge random access memory (CBRAM) characteristics with formation/rupture of Ni conductive filaments (CFs). The Ta-embedded device showed lower forming/SET voltages and initial resistance due to the reduced effective thickness of TaOx films due to the inserted Ta metal layer. In addition, the Ta-embedded device exhibited improved endurance and resistance distribution due to suppression of the random formation of Ni CFs. In this study, Ni/TaOx/NiSi and Ni/TaOx/T/TaOx/NiSi devices were fabricated, and the resistive switching (RS) behaviors were investigated. A 2 nm-thick Ta metal layer was deposited between two TaOx films to form a Ni/TaOx/T/TaOx/NiSi stack, which was analyzed using TEM. Based on a linear scale I-V curve and an R-V graph, both devices showed conventional bipolar conductive bridge random access memory (CBRAM) characteristics with formation/rupture of Ni conductive filaments (CFs). The Ta-embedded device showed lower forming/SET voltages and initial resistance due to the reduced effective thickness of TaOx films due to the inserted Ta metal layer. In addition, the Ta-embedded device exhibited improved endurance and resistance distribution due to suppression of the random formation of Ni CFs.