Charge-Storage Aromatic Amino Compounds for Nonvolatile Organic Transistor Memory Devices

Area of Science:

• Organic electronics
• Materials science
• Nonvolatile memory devices

Background:

• Organic field-effect transistors (OFETs) are explored for nonvolatile memory applications.
• Interfacial engineering is crucial for optimizing charge storage and device performance.
• Self-assembled molecules offer tunable properties for interface modification.

Purpose of the Study:

• To propose novel charge-storage nonvolatile organic field-effect transistor (OFET) memory devices.
• To investigate the role of interfacial self-assembled molecules with varying aromatic amino moieties (PyPN, PN, DPN) on memory performance.
• To correlate molecular structure, interfacial morphology, and energy level alignment with device characteristics.

Main Methods:

• Fabrication of pentacene-based OFET memory devices incorporating functionalized self-assembled molecules (PyPN, PN, DPN) as interface modifiers and charge-storage elements.
• Characterization of memory performance, including memory window and endurance (150 write-read-erase-read cycles).
• Morphology analysis using techniques to confirm interfacial layer aggregation and contact area.
• Computational calculations to determine energy level matching and tunneling barrier characteristics.

Main Results:

• The PyPN-containing device exhibited a significantly larger memory window (48.43 V) compared to PN (24.88 V) and DPN (8.34 V) devices.
• The PyPN device demonstrated stable memory characteristics over 150 cycles.
• Morphology analysis revealed significant aggregation in interfacial layers due to N atomic self-catalysis and hydrogen bonding, leading to full contact with pentacene.
• Optimal energy level alignment between PyPN and pentacene facilitated efficient hole carrier injection.

Conclusions:

• Interfacial self-assembled molecules, particularly PyPN, can effectively enhance charge-storage capabilities in OFET memory devices.
• Molecular aggregation and favorable energy level alignment are key factors for achieving high memory performance and stability.
• The proposed molecular design provides a promising strategy for developing advanced nonvolatile organic memory technologies.