visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
장소 E6 Room(#2501) 
일시 May. 25th (Wed), 14:00 
연사 Dr. Duk-Hyun Choe(Samsung Advanced Institute of Technology) 

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 일시 장소 연사 제목
공지 Sep.22 2022  E6-1 #1323    2022 가을학기 응집물리 및 광학 세미나 전체 일정
416 2010/02/14-05/09  E6, 1501  황철주(주성엔지니어링 사장) 외  Physics Colloquium - 2011 Spring file
415 4pm, 26th May  E6 1323  황민수 (Department of Physics, Korea University)  (광학분야 특별세미나)Topological photonic devices
414 2015/03/09-06/08  E6, 1501  최현용교수(연세대) 외12명  Physics Colloquium : 2015 Spring file
413 4pm, 31th March  online  최현용 (서울대학교 물리천문학부)  (광학분야 특별세미나)Ultrafast time-resolved spectroscopy in topological materials
412 Aug.17 (Wed), 11:00AM  E6-6 #118호  최준희 박사(Caltech IQIM, Postdoctoral Scholar)  Robust Hamiltonian Engineering of Large Quantum Systems (큰 양자시스템의 견고한 해밀토니안 엔지니어링)
411 2010/02/08-05/03  E6, 1501  최인수교수(서울대) 외  Physics Ciolloquium : 2010 Spring file
410 2009/10/21, 4PM  E6, 1501  최석봉교수(서울대)  Interdimensional Universality of Dynamic Interfaces
409 2010/09/06-12/06  E6, 1501  조호진기자(조선일보) 외  Physics Colloquium : 2010 Fall file
408 2017/03/21 - 06/08  Seminar Room 1323  조길영 박사(KAIST) 외  Spring 2017: Physics Seminar Serises file
407 5.16(월),16:00  E6, #1501  조규붕교수 (HKUST)  Design synthetic topological matter with atoms and lights
406 Oct. 15, 4pm  (https://kaist.zoom.us/j/93997220310)  정현석 교수님 (SNU)  Towards resource-efficient and fault-tolerant quantum computation with nonclassical light
405 4. 25(월), 16:00  E6, #1501  정영욱 책임연구원 (한국원자력연구원)  Ultrafast electron beam, a tool to explore the nanoscopic world of materials(우리말강의)
404 Dec. 13-14(Wed.-Thu.) 13:30 PM  자연과학동 대형강의실 (1501호)  장기주 교수 외 9명  KAIST-KIAS Joint Workshop in Theoretical Sciences 개최 file
403 May 21 (Tue.), 4:00 PM  #5318, E6-2  임준원 박사  Classification of flat bands according to the band-crossing singularity of Bloch wave functions file
402 2019/09/02 - 12/09  Seminar Room 1501  이호성 박사 (한국표준과학연구원) and etc.  Fall 2019: Physics Colloquium file
401 2015/10/14, 6PM  KAIST Munji Campus Supex Hall  이창환 교수 (부산대학교 물리학과)  인터스텔라 영화 속의 물리 file
400 3. 28(월), 16:00  E6, #1501  이준희교수 (UNIST 에너지 및 화학공학부)  Ultimate-density atomic semiconductor via flat bands
399 2009/09/07-11/30  E6, 1501  이주영박사(KIAS) 외  Physics Colloquium : 2009 Fall file
398 November 8 (Thu.), 16:00 PM  #1323, E6-2  이종완 박사  Conformality lost file
397 2017/03/06 - 05/29  Seminar Room 1501  이종봉 박사 (POSTECH) 외  Spring 2017: Physics Colloquium file