Abstracts Book - IMRC 2018

• SD6-O005
PROBING NANOSCALE STRUCTURE OF DISORDERED MATERIALS
USING 4-DIMENSIONAL SCANNING TRANSMISSION ELECTRON
MICROSCOPY
Menglin Zhu 1 , Soohyun Im 1 , Michelle Paquette 2 , Nathan Oyler 3 , Paul Rulis 2 , Ridwan Sakidja 4 ,
Jinwoo Hwang 1
1 The Ohio State University, Materials Science and Engineering, United States. 2 University of
Missouri, Department of Physics and Astronomy, United States. 3 University of Missouri,
Department of Chemistry, United States. 4 Missouri State University, Physics, Astronomy, and
Materials Science, United States.
We present a novel electron nanodiffraction technique based on 4-dimensional
scanning transmission electron microscopy (4-D STEM) that can determine the local
structural heterogeneity in nanoscale functional materials. Despite recent advances
in materials characterization, the characterization of complex materials still remains
challenging, especially when the material has low dimensionality and/or includes
significant degree of disorder. We have advanced 4-D STEM, which has been
recently enabled due to the development of fast pixelated STEM detectors, to
determine the nanoscale structure of disordered ceramic thin films for electronic
and functional applications. Using 4-D STEM, we acquire nanodiffraction patterns
from individual nanoscale volume of the sample with spatial oversampling and a
high signal to noise ratio. Subsequent analyses of the nanodiffraction data using
structural fluctuation and angular correlation function can determine the details of
structural heterogeneity at the nanoscale, including the type, size, connection, and
volume fraction of medium range order comprised of the connection of the nearest
neighbor clusters, which has been difficult to achieve using conventional diffraction
or imaging methods in the past. We show that the new information on MRO
precisely correlates to the materials’ important properties, including dielectric
constant and mechanical stability. This promising new characterization method can
therefore advance our understanding on important structure-property
relationships, not only in disordered materials but also in any other nanomaterials
systems where extended defects and structural heterogeneity dictate the
important properties of the system.
Acknowledgment: We acknowledge support from the National Science
Foundation (NSF) DMREF under DMR-1729086.
Keywords: Amorphous, Nanodiffraction, MRO
Presenting authors email: hwang.458@osu.edu