Achieving Forming-Free NbO_x Mott Memristors With High Performance Through Lithium Intercalation

In recent years, niobium oxide (NbO_x)-based Mott memristors have attracted considerable attention due to their promising applications in neuromorphic computing. However, the relatively high voltages required for the electroforming process pose a significant challenge to their large-scale integration. To address this issue, in this work, a thin layer of lithium titanate (Li₄Ti₅O₁₂, LTO) is introduced to intercalate lithium ions into the NbO_x switching layer within a device structured as Pt/LTO/Nb/NbO_x/W/Ti, successfully achieving a forming-free NbO_x Mott memristor. This modification not only enables the forming-free operation but also results in a marked reduction in the threshold current, lowering it to 19μ A, a significant improvement compared to > 100 μ A observed in the control sample without the intercalated layer, thereby substantially reducing energy consumption. Moreover, the composition and migration of Li⁺ ions are elucidated through electron energy loss spectroscopy (EELS). Finally, to demonstrate the practical application of these forming-free memristors, an oscillation circuit is constructed to demonstrate its potential application in artificial neurons.