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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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This content will become publicly available on November 22, 2025
Natural Organic Pectin Polysaccharide Based Resistive Random Access Memory
Nowadays, non-volatile memory technologies have been widely applied in different areas. Of these memory technologies, non-volatile resistive random access memory (ReRAM) is attractive because of its simple device architecture and fabrication process, high scalability and data density, good performances in terms of switching speed, high power efficiency and reasonably wide memory window. In order to address the issues of disposable and degradation of electronic waste by typical ReRAM with the active layer made of inorganic oxide materials and fossil-fuel based polymeric materials, a green and sustainable strategy has been adopted in producing ReRAM by using natural organic-based materials based on protein and carbohydrate, such as honey, fructose, aloe vera, etc. Among these materials, pectin-polysaccharide thin film has demonstrated promising resistive switching characteristics. The two ranges of pectin concentrations that have been investigated are ³5 mg/ml and £1.5 mg/ml, and it showed that pectin with concentration <1.5 mg/ml reveals a higher ON/OFF ratio. However, the resistive switching characteristics with pectin concentration between 1.5 mg/ml and 5 mg/ml have yet been explored and reported. In this work, pectin with concentrations of 1.5~5 mg/ml were prepared from pectin-polysaccharide solution into the active switching layer, and ReRAM devices with such pectin resistive switching layer were fabricated. The pectin-polysaccharide solution, pectin resistive film, and ReRAM devices were systematically investigated. Surface tension and contact angle of pectin-polysaccharide precursor solutions as a function of pectin concentration on the substrate were measured by a goniometer. Surface topography of solidified thin films was characterized by an atomic force microscope (AFM) and a field-emission scanning electron microscope (FE-SEM). Chemical functional groups of the pectin-polysaccharide precursor solutions and solidified thin films were examined by a Fourier transform infrared (FTIR) spectroscopy. The resistive switching behaviors were characterized and compared by electrical measurement. The results show that 4 mg/ml recorded the highest ON/OFF ratio compared to ever reported values, as well as desirable memory window, non-volatility in retention, and stability over 100 cycles. This study proves that pectin-polysaccharide is a promising green and sustainable bio-organic material for non-volatile ReRAM for electronic applications such as in emerging neuromorphic computing systems.
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- PAR ID:
- 10618439
- Publisher / Repository:
- IOP Science
- Date Published:
- Journal Name:
- ECS Meeting Abstracts
- Volume:
- MA2024-02
- Issue:
- 20
- ISSN:
- 2151-2043
- Page Range / eLocation ID:
- 1779 to 1779
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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