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arXiv · 2508.07698

Breakdown and polarization contrasts in ferroelectric devices observed by operando laser-based photoemission electron microscopy with the AC/DC electrical characterization system

Hirokazu Fujiwara·Yuki Itoya·Masaharu Kobayashi·Cédric Bareille·Toshiyuki Taniuchi
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Abstract

We have developed an operando laser-based photoemission electron microscope (laser-PEEM) with a ferroelectric characterization system. A Sawyer-Tower circuit was implemented to measure the polarization-voltage ($P-V$) characteristics of ferroelectric devices. Using this system, we successfully obtained the well-defined $P-V$ hysteresis loops for a ferroelectric capacitor incorporating Hf$_{0.5}$Zr$_{0.5}$O$_2$ (HZO), reproducing the typical field-cycling characteristics of HZO capacitors. After dielectric breakdown caused by field-cycling stress, we visualized a conduction filament through the top electrode without any destructive processing. Additionally, we successfully observed polarization contrast through the top electrode of an oxide semiconductor (InZnO$_x$). These results indicate that our operando laser-PEEM system is a powerful tool for visualizing conduction filaments after dielectric breakdown, the ferroelectric polarization contrasts, and electronic state distribution of materials implemented in ferroelectric devices, including ferroelectric field-effect transistors and ferroelectric tunnel junctions.

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Hirokazu Fujiwara, Yuki Itoya, Masaharu Kobayashi, Cédric Bareille, Toshiyuki Taniuchi. 2025-08-11. Breakdown and polarization contrasts in ferroelectric devices observed by operando laser-based photoemission electron microscopy with the AC/DC electrical characterization system. https://arxiv.org/abs/2508.07698

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