Polarization fluctuation dominated electrical transport processes of polymer based ferroelectric-field-effect transistors

TL;DR

This study investigates how polarization fluctuations influence electrical transport in ferroelectric FETs, revealing temperature-dependent dielectric changes and distinct transport regimes driven by polarization dynamics.

Contribution

It demonstrates that polarization fluctuations, rather than static dipolar disorder, dominate transport processes in ferroelectric FETs, providing new insights into their temperature-dependent behavior.

Findings

Dielectric constant varies significantly with temperature near ferroelectric transition.

Polarization fluctuations dominate over static dipolar disorder in transport.

Distinct transport regimes are observed at different temperatures.

Abstract

Ferroelectric field-effect transistors (FE-FETs) consisting of tunable dielectric layers are utilized to investigate interfacial transport processes. Large changes in the dielectric constant as a function of temperature are observed in FE-FETs in conjunction with the ferroelectric to paraelectric transition. The devices offer a test bed to evaluate specific effects of polarization on the electrical processes. FE-FETs have dominant contributions from polarization-fluctuation rather than static dipolar disorder prevalent in high k paraelectric dielectric-based FETs. Additionally, photo-excitation measurements in the depletion mode reveal clear features in the FET response at different temperatures, indicative of different transport regimes.