Memristive Devices with Multiple Resistance States Based on the Migration of Protons in α‐MoO₃/SrCoO_2.5 Stacks

Abstract

Memristive devices are building blocks for neuromorphic computing. However, non‐ideal properties of memristive devices, such as bad retention, small number of resistance states, and nonlinear pulse programming hinder the development of neuromorphic computation. Based on proton migration in the α‐MoO3/SrCoO2.5 stack, a Pt/α‐MoO3/SrCoO2.5/Nb‐SrTiO3 memristive device is developed with multiple resistance states and excellent nonvolatility. When protons migrate from α‐MoO3 to the SrCoO2.5 lattice, both layers undergo a resistance increase, due to a reduced doping level in α‐MoO3 along with the loss of protons, and a larger direct bandgap of SrCoO2.5 resulted from the insertion of protons. While protons migrate from SrCoO2.5 to α‐MoO3, the device resistance decreases, because of the increased proton concentration in α‐MoO3 and the decreased proton concentration in the SrCoO2.5 layer. The device also realizes nearly linear potentiation and depression under appropriate pulse schemes. A three‐layer backpropagation neural network constructed with the memristive devices acquires an accuracy of 94.3% for the recognition of MNIST handwritten digits.

Ultra-high resistive switching current ratio and improved ferroelectricity and dielectric tunability performance in a BaTiO3/La0.7Sr0.3MnO3 heterostructure by inserting a SrCoO2.5 layer

“…6, the BTO/SCO/LSMO bilayers show superior performance compared with other BTO-based films. 26,27,29,34,51–54 In the reliability test, no damage or breakdown of the Pt/BTO/LSMO and Pt/BTO/SCO/LSMO devices was found, as shown in Fig. 5c.…”

Review of solid-state proton devices for neuromorphic information processing

“…A two terminal vertical protonic memristive device was reported by Wang et al 39) as shown in Fig. 8 illustrates memory cycling.…”

“…5(c)], bottom electrode act as drain and buried inside proton conductor. [39][40][41][42] In this case, either top electrode or a dedicated layer (placed between top electrode and proton conductor) may act as a source for proton reservoir. By applying electric field between two terminals, migration of protons can be controlled inside proton conducting layer.…”

Filament-free memristors for computing

“…Depending on the arrangement of atoms, different phases can coexist in solid form, e.g., anatase and rutile phases in TiO 2 [ 116 , 117 ]. Structural changes between phases induce changes in the band structure of the material, resulting in changes in its electrical properties [ 118 – 126 ]. Materials that exhibit a reversible phase transition upon electrical stimulation can be utilized as a memristor.…”