High-speed energy-efficient memristor confined in sub-5 nm space with elemental oxygen reservoir layer

Abstract

Abstract Random migration of oxygen vacancies (V O ) leads to unpredictable formation and rupture of conductive filaments (CFs) in oxide-based memristors. In this work, an atomically flat 4.5 nm hafnium oxide (HfO x ) switching layer and a 3.5 nm elemental oxygen reservoir (EOR) layer are confined between two-dimensional HfS 2 and MoS 2 layers, ensuring a homogeneous electric field distribution. The migration and redistribution of V O within the ultrathin HfO x switching layer enable the memristive behavior of the device. The EOR-based memristors achieve high set/reset transition speeds of 8 ns and 15 ns, respectively. The electroneutral EOR layer interacts with V O in the HfO x switching layer and, together with the HfO x tunnel layer above the HfS 2 , forms a barrier to suppress the high-resistance state current. Reliable endurance up to 10 5 cycles, and long retention up to 10 5  s are simultaneously obtained. Finally, a high recognition accuracy of 97.0% is achieved, demonstrating potential for low-power neuromorphic computing applications.