Thermal-dependent nonvolatile memory characteristics based on organic ferroelectric field-effect transistor

Area of Science:

• Organic electronics
• Materials science
• Solid-state physics

Background:

• Organic ferroelectric field-effect transistors (OFeFETs) offer potential for nonvolatile memory applications.
• The ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] is a key material in OFeFETs.
• Understanding thermal stability is crucial for device reliability and performance.

Purpose of the Study:

• To investigate the impact of thermal annealing on the nonvolatile memory characteristics of pentacene-based OFeFETs.
• To determine the critical temperature threshold affecting memory performance.
• To correlate thermal-induced phase transitions in P(VDF-TrFE) with device behavior.

Main Methods:

• Fabrication of pentacene-based OFeFET devices.
• Controlled thermal annealing of devices at various temperatures.
• Characterization of nonvolatile memory properties, including memory window and on-off ratio.

Main Results:

• OFeFETs annealed up to 80°C showed stable memory characteristics.
• Annealing temperatures beyond 80°C led to a monotonic reduction in memory performance.
• The observed degradation correlated with the phase transition of P(VDF-TrFE) from ferroelectric beta-phase to paraelectric gamma-phase.

Conclusions:

• The Curie temperature of P(VDF-TrFE) is critical for maintaining nonvolatile memory characteristics in OFeFETs.
• Thermal annealing beyond the phase transition temperature negatively impacts device performance.
• Phase transition management is essential for tailoring electric characteristics in OFeFETs.