The stabilization of the threshold switching characteristics of memristive [Formula: see text] is examined as a function of sample growth and device characteristics. Sub-stoichiometric [Formula: see text] was deposited via magnetron sputtering and patterned in nanoscale ([Formula: see text]–[Formula: see text]) W/Ir/[Formula: see text]/TiN devices and microscale ([Formula: see text]–[Formula: see text]) crossbar Au/Ru/[Formula: see text]/Pt devices. Annealing the nanoscale devices at 700 [Formula: see text]C removed the need for electroforming the devices. The smallest nanoscale devices showed a large asymmetry in the IV curves for positive and negative bias that switched to symmetric behavior for the larger and microscale devices. Electroforming the microscale crossbar devices created conducting [Formula: see text] filaments with symmetric IV curves whose behavior did not change as the device area increased. The smallest devices showed the largest threshold voltages and most stable threshold switching. As the nanoscale device area increased, the resistance of the devices scaled with the area as [Formula: see text], indicating a crystallized bulk [Formula: see text] device. When the nanoscale device size was comparable to the size of the filaments, the annealed nanoscale devices showed similar electrical responses as the electroformed microscale crossbar devices, indicating filament-like behavior in even annealed devices withoutmore »
Scalable 3D Ta:SiO x Memristive Devices
A highly reliable memristive device based on tantalum‐doped silicon oxide is reported, which exhibits high uniformity, robust endurance (≈1 × 109 cycles), fast switching speed, long retention, and analog conductance modulation. Devices with junction areas ranging from microscale to as small as 60 × 15 nm2 are 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.
- Award ID(s):
- 1740248
- Publication Date:
- NSF-PAR ID:
- 10112107
- Journal Name:
- Advanced Electronic Materials
- Volume:
- 5
- Page Range or eLocation-ID:
- 1800958
- ISSN:
- 2199-160X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Publisher's Version of Record
- https://doi.org/10.1002/aelm.201800958
