Abstract The development of next‐generation in‐memory and neuromorphic computing can be realized with memory transistors based on 2D ferroelectric semiconductors. Among these, In2Se3is the interesting since it possesses ferroelectricity in 2D quintuple layers. Synthesis of large amounts of In2Se3crystals with the desired phase, however, has not been previously achieved. Here, the gram‐scale synthesis of α‐In2Se3crystals using a flash‐within‐flash Joule heating method is demonstrated. This approach allows the synthesis of single‐phase α‐In2Se3crystals regardless of the conductance of precursors in the inner tube and enables the synthesis of gram‐scale quantities of α‐In2Se3crystals. Then, α‐In2Se3flakes are fabricated and used as a 2D ferroelectric semiconductor FET artificial synaptic device platform. By modulating the degree of polarization in α‐In2Se3flakes according to the gate electrical pulses, these devices exhibit distinct essential synaptic behaviors. Their synaptic performance shows excellent and robust reliability under repeated electrical pulses. Finally, it is demonstrated that the synaptic devices achieve an estimated learning accuracy of up to ≈87% for Modified National Institute of Standards and Technology patterns in a single‐layer neural network system.
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Highly Efficient Polarization‐Controlled Electrical Conductance Modulation in a van der Waals Ferroelectric/Semiconductor Heterostructure
Abstract Utilizing the unique in‐plane/out‐of‐plane polarization coupling in ferroelectric van der Waals α‐In2Se3, ferroelectric‐polarization‐controlled electrical conductance modulation in two‐dimensional (2D) MoS2with a large dynamic range of over 5 orders of magnitude and excellent non‐volatility is demonstrated. This highly efficient control of the electrical conductance is facilitated by enhanced capacitive coupling through atomic‐layer‐deposition‐grown Al2O3as the dielectric medium. By varying the in‐plane poling bias to the ferroelectric α‐In2Se3, the electrical conductance of vertically stacked 2D MoS2can be tuned continuously. This approach enables simplified device design and provides great flexibility in device integrations, and it can be applied in principle to manipulate the electronic states in any 2D semiconductors for various applications such as transistors, tunneling devices, and reconfigurable electronics. The results also provide insight into the ferroelectric polarization screening by ambient chemical species, highlighting the need for surface passivation, and/or device encapsulations.
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- Award ID(s):
- 1930769
- PAR ID:
- 10474226
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Electronic Materials
- Volume:
- 8
- Issue:
- 9
- ISSN:
- 2199-160X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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