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Resistive switching devices are promising candidates for the next generation of nonvolatile memory and neuromorphic computing applications. Despite the advantages in retention and on/off ratio, filamentary-based memristors still suffer from challenges, particularly endurance (flash being a benchmark system showing 104to 106 cycles) and uniformity. Here, we use WO3as a complementary metal-oxide semiconductor–compatible switching oxide and demonstrate a proof-of-concept materials design approach to enhance endurance and device-to-device uniformity in WO3-based memristive devices while preserving other performance metrics. These devices show stable resistive switching behavior with >106 cycles, >105-second retention, >10 on/off ratio, and good device-to-device uniformity, without using current compliance. All these metrics are achieved using a one-step pulsed laser deposition process to create self-assembled nanocomposite thin films that have regular guided filaments of ≈100-nanometer pitch, preformed between WO3grains and interspersed smaller Ce2O3grains.
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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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