Resistive switching of Sn-doped In₂O₃/HfO₂ core–shell nanowire: geometry architecture engineering for nonvolatile memory

Abstract

Core-shell NWs offer an innovative approach to achieve nanoscale metal-insulator-metal (MIM) heterostructures along the wire radial direction, realizing three-dimensional geometry architecture rather than planar type thin film devices. This work demonstrated the tunable resistive switching characteristics of ITO/HfO core-shell nanowires with controllable shell thicknesses by the atomic layer deposition (ALD) process for the first time. Compared to planar HfO thin film device configuration, ITO/HfO core-shell nanowire shows a prominent resistive memory behavior, including lower power consumption with a smaller SET voltage of ∼0.6 V and better switching voltage uniformity with variations (standard deviation(σ)/mean value (μ)) of V and V from 0.38 to 0.14 and from 0.33 to 0.05 for ITO/HfO core-shell nanowire and planar HfO thin film, respectively. In addition, endurance over 10 cycles resulting from the local electric field enhancement can be achieved, which is attributed to geometry architecture engineering. The concept of geometry architecture engineering provides a promising strategy to modify the electric-field distribution for solving the non-uniformity issue of future RRAM.

Recent Developments and Perspectives for Memristive Devices Based on Metal Oxide Nanowires

“…This property can be exploited to realize multiple electrodes on a single NW, thus realizing a multitude of resistive switching cells with comparable characteristics on the same NW. A similar mechanism of switching along the axial direction was proposed by Huang et al by considering conductive indium tin oxide (ITO) single crystal NWs covered with an HfO 2 shell layer. Interestingly, the amorphous shell layer was here realized by means of atomic layer deposition (ALD).…”

“…However, in this case electrodes were all deposited on the Ga 2 O 3 insulating shell layer without direct access to the Au inner core. A similar mechanism of switching along the axial direction was proposed by Huang et al [206] by considering conductive indium tin oxide (ITO) single crystal NWs covered with an HfO 2 shell layer. Since in this case the switching events are located in the shell layer along the axial direction of the NW, while the inner conductive core acts only as a conductor channel, the electrode spacing is not a crucial parameter for resistive switching behavior.…”

Binarized Neural Network with Silicon Nanosheet Synaptic Transistors for Supervised Pattern Classification

“…Although several methods for precise adjustment of the analog weight have been proposed 25–27 , these methods require a specially designed pulse waveform and impractical complex peripheral circuitry. In addition, recent memristors exhibit improved reliability 28–30 , but the fabrication process of the device is complex or the materials used are incompatible with conventional silicon processes, is a critical obstacle to the design of peripheral circuits.…”

A Triode Device with a Gate Controllable Schottky Barrier: Germanium Nanowire Transistors and Their Applications

“…The high performance of modern electronics results from the fine control of charge transport that can be achieved, beginning with charge injection into an active channel and its transfer through an electrical contact . In the manufacture of reliable electronics, problems of contact resistances rising from metal–semiconductor interfaces are inevitable.…”