Nanoscale Phase and Orientation Mapping in Multiphase Polycrystalline Hafnium Zirconium Oxide Thin Films Using...

Area of Science:

• Materials Science
• Solid State Physics
• Nanotechnology

Background:

• Ferroelectric hafnium zirconium oxide (HZO) is a promising material for advanced memory and transistors.
• The metastable nature of HZO's polar phase presents challenges in characterizing its multiphase structure.
• Accurate phase-specific analysis is difficult due to structural similarities and nanoscale dimensions.

Purpose of the Study:

• To demonstrate a novel characterization approach for multiphase polycrystalline HZO thin films.
• To enable accurate measurement of crystallographic phase and orientation in HZO.
• To facilitate robust analysis of HZO film structure for device optimization.

Main Methods:

• Application of 4D scanning transmission electron microscopy (4D-STEM).
• Automated electron diffraction pattern indexing for crystallographic analysis.
• Characterization of large working areas (hundreds of nanometers).

Main Results:

• Quantitative and statistically robust analysis of HZO film composition and structure.
• Identification of phase composition, polarization axis alignment, and phase distribution.
• Successful characterization of multiphase polycrystalline HZO films.

Conclusions:

• 4D-STEM with automated indexing provides a powerful framework for analyzing HZO.
• This method enables reliable characterization of process-structure-property relationships in HZO.
• Accelerates optimization and implementation of ferroelectric HZO in electronic devices.