• Shimizu, Takao
• Hiranaga, Yoshiomi
• Funakubo, Hiroshi
• Mimura, Takanori
• Cho, Yasuo

Abstract

<jats:title>Abstract</jats:title><jats:p>The asymmetry in the capacitance–voltage (<jats:italic>C</jats:italic>–<jats:italic>V</jats:italic>) curves obtained from a ferroelectric material can provide information concerning the internal microstructure of a specimen. The present study visualized nanoscale switching of a HfO<jats:sub>2</jats:sub>-based ferroelectric thin film in real space based on assessing asymmetry using a local <jats:italic>C</jats:italic>–<jats:italic>V</jats:italic> mapping method. Several parameters were extracted from the local <jats:italic>C</jats:italic>–<jats:italic>V</jats:italic> curves at each point. The parameter <jats:italic>V</jats:italic><jats:sub><jats:italic>i</jats:italic></jats:sub>, indicating the lateral shift of the local <jats:italic>C</jats:italic>–<jats:italic>V</jats:italic> curve, was employed as an indicator of local imprint. In addition, the differences in the areas between the <jats:italic>C</jats:italic>–<jats:italic>V</jats:italic> curves for the forward and reverse sweeps, <jats:italic>S</jats:italic><jats:sub>f</jats:sub> − <jats:italic>S</jats:italic><jats:sub>r</jats:sub>, provided another slightly different indicator of nanoscale switching asymmetry. These parameters obtained from asymmetric <jats:italic>C</jats:italic>–<jats:italic>V</jats:italic> curves are thought to be related to internal electric fields and local stress caused by defects in the film. The work reported here also involved a cluster analysis of the extracted parameters using the <jats:italic>k</jats:italic>-means method.</jats:p>

Topics

• microstructure
• cluster
• thin film
• defect