Enhancement of resistive switching properties in Al₂O₃bilayer-based atomic switches: multilevel resistive switching

Abstract

Atomic switches are considered to be building blocks for future non-volatile data storage and internet of things. However, obtaining device structures capable of ultrahigh density data storage, high endurance, and long data retention, and more importantly, understanding the switching mechanisms are still a challenge for atomic switches. Here, we achieved improved resistive switching performance in a bilayer structure containing aluminum oxide, with an oxygen-deficient oxide as the top switching layer and stoichiometric oxide as the bottom switching layer, using atomic layer deposition. This bilayer device showed a high on/off ratio (10) with better endurance (∼2000 cycles) and longer data retention (10 s) than single-oxide layers. In addition, depending on the compliance current, the bilayer device could be operated in four different resistance states. Furthermore, the depth profiles of the hourglass-shaped conductive filament of the bilayer device was observed by conductive atomic force microscopy.

Synaptic Characteristics from Homogeneous Resistive Switching in Pt/Al2O3/TiN Stack

“…We will discuss more about the self-compliance effect on the synaptic behavior in the pulse switching mode. The homogeneous switching (type 3) can be obtained by using a negative differential resistance effect before the electroforming or set processes ( Figure S1 ) [ 34 , 46 ]. The initial reset process in a negative bias occurs probably because of the abundant initial traps in the Al 2 O 3 layer.…”

Highly Uniform Resistive Switching in HfO2 Films Embedded with Ordered Metal Nanoisland Arrays

“…As conductive filaments dictate both the location and mechanism of transport, and ultimately enables information storage and multi-functionality, obtaining spatially-resolved information involving their construction is required to maximize the enhancements in performance. Three-dimensional conductive-AFM (3D c-AFM) tomography, [51][52][53][54] a recently developed AFM approach, combines the sensitive force control in the zdimension of the AFM with a hard, conductive diamond probe attached to a high stiffness cantilever (~ 50 N/m) to sequentially remove material layer-by-layer and subsequently measure the local current, thus yielding a slice-and-view approach to observe conductive filaments within oxide-based memristors.…”

Facile synthesis of nickel cobaltite quasi-hexagonal nanosheets for multilevel resistive switching and synaptic learning applications

“…A clear trend in the ±V STOP voltagedependent I SET , I RESET , V SET , and V RESET was observed from the experimental data. These results indicated that the size of the conductive filament was modulated as a function of CC 47 . The nature of RS properties can be elucidated by the value of η (I SET /I CC ) or (I RESET /I CC ).…”