visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2022-05-25 14:00 
연사  
장소 E6 Room(#2501) 

Physics Seminar

 

 

 

Atomic-level insights into ferroelectric switching and preferred orientation of ultrathin hafnia

 

Duk-Hyun Choe

Samsung Advanced Institute of Technology

May. 25th (Wed), 14:00, E6 Room(#2501)

 

Over the past decade there has been a resurgence of interest in ferroelectric (FE) devices in the semiconductor device community. This interest was sparked by the discovery of ferroelectricity in a simple binary oxide, hafnia. Unlike conventional FE perovskite, FE hafnia exhibits ultra-scalable ferroelectricity compatible with Si electronics, providing an unprecedented opportunity for the use of FEs in advanced memory and logic devices. Many proof-of-concept devices based on FE hafnia are indeed showing some promise. However, their practical engineering is still largely relying on trial-and-error process that lacks a clear theoretical guidance, and it remains challenging to rationally design the FE devices for targeted applications. Thus, the community is now calling for more fundamental investigations on the physics of ferroelectricity in hafnia.

In this presentation, we briefly review the status of the field and provide our new understanding on FE switching and surface stability of hafnia. We will first introduce an ultralow FE switching mechanism that can enable rapid growth of the FE domains in hafnia [1]. We also establish a new class of topological domain walls in HfO2, which can help understand complex domain structures often present in FE hafnia samples. Next, we present our systematic study of surface-functionalized FE hafnia [2]. We show that their remnant polarization (Pr) and coercive field (Ec) can strongly depend on the surface treatments, providing a possible explanation for the enhancement of Pr in ultrathin hafnia with preferred orientation [3,4]. We believe our study represents an important step towards bridging the gap between practical engineering and the first-principles simulations in the field of FE hafnia.

 

[1] D.-H. Choe et al., Mater. Today 50, 8 (2021).

[2] D.-H. Choe et al., IEDM (2021).

[3] S. S. Cheema et. al., Nature 580, 478 (2020)

[4] H. Lee, D.-H. Choe, S. Jo 36499 (2021).13,  ACS Appl. Mater. Interfaces et. al.,

 

Contact: Prof. Chan-Ho Yang (chyang@kaist.ac.kr) ,

Departmentof Physics / Center for Lattice Defectronics

 

Department of Physics, KAIST

번호 날짜 연사 제목
공지 2025-02-24 16:00    2025년 봄학기 콜로키움 안내
공지 2025-02-27 16:00    2025년 봄 물리학과 특별세미나 (광학/응집물리 분야)
205 2019-06-17 10:30    Chiral Spintronics file
204 2015-07-15 14:00    Electronic and optical properties of titanate-based oxide superlattices
203 2016-09-29 16:00    Large-scale Silicon Photonic MEMS Switches
202 2017-03-24 16:00    Graphene based nano electronics and nano electromechanics; focusing on precise control of nano structures for studying accurate physical properties
201 2022-06-10 16:00    Fe5GeTe2의 나선형 자성특성과 자기저항의 전류밀도 의존성 연구 file
200 2025-01-08 16:00  Dr. SangEun Han  Quantum impurity model for two-stage multipolar ordering and Fermi surface reconstruction
199 2015-12-03 16:00    Hybrid solid state spin qubits in wide bandgap semiconductors
198 2017-06-02 16:00    Maxwell's demon in quantum wonderland file
197 2022-11-09 16:00    Radio Astronomy, Radio Interferometry, and Multi-wavelength Studies on Relativistic Jets
196 2023-05-03 16:00    Probing microscopic origins of axions by the chiral magnetic effect
195 2020-10-15 17:00    Time crystals, quasicrystals, and time crystal dynamics in the superfluid universe file
194 2022-03-31 10:00    Weiss fields for Quantum Spin Dynamics file
193 2022-03-29 10:00    Non-reciprocal phase transitions file
192 2024-05-16 14:30    [Astrophysics Seminar] Observational Cosmology with Superconducting Sensors
191 2024-05-30 10:00    Quasiperiodic Effects in Quasicrystals
190 2018-11-09 14:30    Moiré superlattices – from twisted bilayer graphene to quasicrystal file
189 2015-10-16 15:00    High Magnetic Fields to Probe the sub-eV range of Particle/Astroparticle Physics - From the OSQAR experiments at CERN up to new perspectives at LNCMI-Grenoble
188 2018-07-02 15:00    High Precision Magnetic Field Measurement for the Muon g-2 Experiment file
187 2016-06-01 10:30    Welcome to Nature Photonics
186 2025-04-22 16:00  Dr. Nanse Esaki (The University of Tokyo)  Spin Nernst and thermal Hall effects of topological triplons in quantum dimer magnets on the maple-leaf and star lattices file