On the structural origins of ferroelectricity in HfO{sub 2} thin films

Journal Article · Mon Apr 20 00:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4919135· OSTI ID:22398933

Sang, Xiahan; Grimley, Everett D.; LeBeau, James M. ^[1]; Schenk, Tony; Schroeder, Uwe ^[2]

---

1. Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695-7907 (United States)
2. NaMLab gGmbH/TU Dresden, Noethnitzer Str. 64, Dresden D-01187 (Germany)

Here, we present a structural study on the origin of ferroelectricity in Gd doped HfO{sub 2} thin films. We apply aberration corrected high-angle annular dark-field scanning transmission electron microscopy to directly determine the underlying lattice type using projected atom positions and measured lattice parameters. Furthermore, we apply nanoscale electron diffraction methods to visualize the crystal symmetry elements. Combined, the experimental results provide unambiguous evidence for the existence of a non-centrosymmetric orthorhombic phase that can support spontaneous polarization, resolving the origin of ferroelectricity in HfO{sub 2} thin films.

• OSTI ID: 22398933
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 16 Vol. 106; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ATOMS
CRYSTALS
DOPED MATERIALS
ELECTRON DIFFRACTION
GADOLINIUM COMPOUNDS
HAFNIUM OXIDES
LATTICE PARAMETERS
NANOSTRUCTURES
ORTHORHOMBIC LATTICES
POLARIZATION
SYMMETRY
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY