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Updated: Oct 21, 2025
11:10
Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
12.1K
Inherent stochasticity during insulator-metal transition in VO2.
Shaobo Cheng1, Min-Han Lee2,3, Richard Tran4
1Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973.
Summary
Vanadium dioxide (VO2) shows stochastic switching for neuromorphic computing. Microscopic studies reveal structural variations during its phase transition, aiding understanding of its use in neuron-like devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Vanadium dioxide (VO2) exhibits a near-room-temperature insulator-metal transition, crucial for neuromorphic computing.
- Its volatile switching property mimics neuron spiking, but nanoscale structural stochasticity during phase transitions remains understudied.
Purpose of the Study:
- To investigate nanoscale structural stochasticity in VO2 during its phase transition.
- To characterize the structural changes in VO2 at local areas within a device configuration.
- To understand the volatile switching mechanisms for neuromorphic applications.
Main Methods:
- In situ transmission electron microscopy (TEM) for real-time observation.
- Ex situ resistive switching measurements.
- Analysis of structural phase transitions between monoclinic and rutile VO2 phases.
Main Results:
- Characterization of the VO2 phase transition between monoclinic and rutile structures under electrical bias.
- Observation of varied VO2 monoclinic crystal orientations after each resistive switching cycle.
- Demonstration of stochastic cycle-to-cycle variations in volatile resistive switching.
Conclusions:
- Microscopic studies reveal the stochastic nature of VO2 volatile switching.
- Understanding in-plane structural anisotropy is key to VO2-based neuromorphic devices.
- These findings advance the comprehension of VO2 switching mechanisms for neuromorphic computing.
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