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Abstract In this paper, natural organic honey embedded with carbon nanotubes (CNTs) was studied as a resistive switching material for biodegradable nonvolatile memory in emerging neuromorphic systems. CNTs were dispersed in a honey-water solution with the concentration of 0.2 wt% CNT and 30 wt% honey. The final honey-CNT-water mixture was spin-coated and dried into a thin film sandwiched in between Cu bottom electrode and Al top electrode to form a honey-CNT based resistive switching memory (RSM). Surface morphology, electrical characteristics and current conduction mechanism were investigated. The results show that although CNTs formed agglomerations in the dried honey-CNT film, both switching speed and the stability in SET and RESET process of honey-CNT RSM were improved. The mechanism of current conduction in CNT is governed by Ohm’s law in low-resistance state and the low-voltage range in high-resistance state, but transits to the space charge limited conduction at high voltages approaching the SET voltage.
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Resistive Switching Characteristics of Fullerene (C60) in Polymannose Thin Film
The effects of C60 incorporated in polymannose‐based resistive switching memory have been systematically investigated for the first time in bioorganic‐based resistive switching memory. C60 with different concentrations (0–7 wt%) is dispersed in polymannose precursor, drop‐casted on ITO/PET substrate, and dried to form a thin film. Electrochemically inert Au–Pd is used as top electrode. The devices with embedded C60 show better endurance and stability. Read memory window decreases and ON/OFF ratio increases as the concentration of C60 increases. Stable retention time up to 10 years is achieved for all of the devices except the one with 7 wt% C60. Based on zeta potential measurement, polymannose is more negatively charged than C60. Hence, C60 functions as an effective interlock that bridges between long molecular chains of polymannose and enhances the resistive switching properties of the polymannose thin film.
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- Award ID(s):
- 2104976
- PAR ID:
- 10371831
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- physica status solidi (RRL) – Rapid Research Letters
- Volume:
- 16
- Issue:
- 12
- ISSN:
- 1862-6254
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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