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Abstract 2D materials have been of considerable interest as new materials for device applications. Non‐volatile resistive switching applications of MoS2and WS2have been previously demonstrated; however, these applications are dramatically limited by high temperatures and extended times needed for the large‐area synthesis of 2D materials on crystalline substrates. The experimental results demonstrate a one‐step sulfurization method to synthesize MoS2and WS2at 550 °C in 15 min on sapphire wafers. Furthermore, a large area transfer of the synthesized thin films to SiO2/Si substrates is achieved. Following this, MoS2and WS2memristors are fabricated that exhibit stable non‐volatile switching and a satisfactory large on/off current ratio (103–105) with good uniformity. Tuning the sulfurization parameters (temperature and metal precursor thickness) is found to be a straightforward and effective strategy to improve the performance of the memristors. The demonstration of large‐scale MoS2and WS2memristors with a one‐step low‐temperature sulfurization method with simple strategy to tuning can lead to potential applications such as flexible memory and neuromorphic computing.
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Scalable 3D Ta:SiO x Memristive Devices
Abstract A highly reliable memristive device based on tantalum‐doped silicon oxide is reported, which exhibits high uniformity, robust endurance (≈1 × 109cycles), fast switching speed, long retention, and analog conductance modulation. Devices with junction areas ranging from microscale to as small as 60 × 15 nm2are fabricated and electrically characterized. ON‐/OFF‐ conductance and reset current show weak area dependence when the device is relatively large, and they become proportional to the device area when further scaled down. Two‐layer devices with repeatable switching behavior are achieved. The current study shows the potentials of Ta:SiO2‐based 3D vertical devices for memory and computing applications. It also suggests that doping of the switching layer is an efficient approach to engineer the performance of memristive devices.
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- Award ID(s):
- 1740248
- PAR ID:
- 10460665
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Electronic Materials
- Volume:
- 5
- Issue:
- 9
- ISSN:
- 2199-160X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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