TY  - JOUR
T1  - Origin of ferroelectric-like orthorhombic phase in oxygen-deficient HfO2–y nanoparticles
AU  - Eliseev, E.A.
AU  - Kondakova, I.V.
AU  - Zagorodniy, Yu.O.
AU  - Shevliakova, H.V.
AU  - Leshchenko, O.V.
AU  - Pavlikov, V.N.
AU  - Yurchenko, L.P.
AU  - Karpets, M.V.
AU  - Morozovska, A.N.
JO  - Semiconductor Physics, Quantum Electronics & Optoelectronics
VL  - 28
IS  - 2
SP  - 134
EP  - 141
PY  - 2025
DO  - 10.15407/spqeo28.02.134
UR  - https://doi.org/10.15407/spqeo28.02.134
AB  - In this work, the relationship between the crystalline structure symmetry, concentration of point defects and possible appearance of ferroelectric-like polarization in HfO2–y nanoparticles was established. The X-ray diffraction and electron paramagnetic resonance analyses revealed the formation of ferroelectric-like orthorhombic phase in oxygen-deficient HfO2–y nanoparticles (pure and doped with rare-earth element yttrium ones). Density functional theory (DFT) calculations showed that small HfO2 nanoparticles may become polar, especially in the presence of impurity atoms and/or oxygen vacancies. To explain the experimental results, we modified the effective Landau–Ginzburg–Devonshire (LGD) model using the parameterization approach, focusing on the Landau expansion coefficients associated with polar and antipolar orderings, which agrees with the performed DFT calculations. The effective LGD model may be useful for developing silicon-compatible ferroelectric nanomaterials based on HfxZr1–xO2–y.
KW  - nanoparticles
KW  - hafnium oxide
KW  - oxygen vacancies
KW  - rare-earth element doping
KW  - ferroelectric-like polar phase
KW  - silicon-compatible ferroelectric nanomaterials
ER  -