TY - GEN

T1 - Optimal Structure of Lanthanum-Doped Hafnium Oxide: First-Principle Modeling

AU - Kovzik, Valeriya M.

AU - Perevalov, Timofey V.

AU - Islamov, Damir R.

N1 - Funding Information: This work was supported by the Russian Science Foundation, grant No. 22-22-00634. Publisher Copyright: © 2022 IEEE.

PY - 2022

Y1 - 2022

N2 - The atomic and electronic structure of lanthanum-doped hafnium oxide (HfO2: La) is studied within the density functional theory simulation. HfO2: La is a promising material for resistive and ferroelectric random-access memory elements. By considering all possible spatial configurations of the oxygen vacancy and two lanthanum atoms in the hafnium substitution position in 95-atom supercell of five crystalline phases of HfO2, the energetically optimal structures of HfO2: La were found. For these structures of crystalline HfO2 with the 2.1 at. % La content the La atoms are located at a distance of about 5.8 Å from each other, and at least one of the lanthanum atoms is distanced from the oxygen vacancy. These structures are characterized by a bandgap free from defect levels, and the bandgap value is almost the same as that of perfect crystals. It is shown that the presence of La and hydrostatic pressure facilitates the stabilization of the ferroelectric and tetragonal phases of HfO2, but these phases remain energetically unfavorable as a bulk crystal.

AB - The atomic and electronic structure of lanthanum-doped hafnium oxide (HfO2: La) is studied within the density functional theory simulation. HfO2: La is a promising material for resistive and ferroelectric random-access memory elements. By considering all possible spatial configurations of the oxygen vacancy and two lanthanum atoms in the hafnium substitution position in 95-atom supercell of five crystalline phases of HfO2, the energetically optimal structures of HfO2: La were found. For these structures of crystalline HfO2 with the 2.1 at. % La content the La atoms are located at a distance of about 5.8 Å from each other, and at least one of the lanthanum atoms is distanced from the oxygen vacancy. These structures are characterized by a bandgap free from defect levels, and the bandgap value is almost the same as that of perfect crystals. It is shown that the presence of La and hydrostatic pressure facilitates the stabilization of the ferroelectric and tetragonal phases of HfO2, but these phases remain energetically unfavorable as a bulk crystal.

KW - alloying impurity

KW - density functional theory

KW - electronic structure

KW - hafnium oxide

KW - oxygen vacancy

KW - quantum chemical simulation

KW - resistive memory

UR - http://www.scopus.com/inward/record.url?scp=85137349348&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/7b362ba5-9502-3299-a875-d493977454ca/

U2 - 10.1109/EDM55285.2022.9855173

DO - 10.1109/EDM55285.2022.9855173

M3 - Conference contribution

AN - SCOPUS:85137349348

SN - 9781665498043

T3 - International Conference of Young Specialists on Micro/Nanotechnologies and Electron Devices, EDM

SP - 11

EP - 14

BT - Proceedings of the 2022 IEEE 23rd International Conference of Young Professionals in Electron Devices and Materials, EDM 2022

PB - IEEE Computer Society

T2 - 23rd IEEE International Conference of Young Professionals in Electron Devices and Materials, EDM 2022

Y2 - 30 June 2022 through 4 July 2022

ER -