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Metastable Phase Formation and Materials Discovery in Complex Oxide Thin Films via Laser Spike Annealing- [electronic resource]
Metastable Phase Formation and Materials Discovery in Complex Oxide Thin Films via Laser Spike Annealing- [electronic resource]
상세정보
- 자료유형
- 학위논문파일 국외
- 최종처리일시
- 20240214101637
- ISBN
- 9798380316903
- DDC
- 620.11
- 저자명
- Connolly, Aine.
- 서명/저자
- Metastable Phase Formation and Materials Discovery in Complex Oxide Thin Films via Laser Spike Annealing - [electronic resource]
- 발행사항
- [S.l.]: : Cornell University., 2023
- 발행사항
- Ann Arbor : : ProQuest Dissertations & Theses,, 2023
- 형태사항
- 1 online resource(152 p.)
- 주기사항
- Source: Dissertations Abstracts International, Volume: 85-03, Section: B.
- 주기사항
- Advisor: Thompson, Michael O.
- 학위논문주기
- Thesis (Ph.D.)--Cornell University, 2023.
- 사용제한주기
- This item must not be sold to any third party vendors.
- 초록/해제
- 요약Rapid thermal processing of materials, particularly processing techniques with high quench rates, have been demonstrated to form and stabilize ambient quenched non-equilibrium metastable phases. These phases often have distinct structures and properties, dramatically expanding the materials space available for applications. One such technique is Laser Spike Annealing (LSA), where a scanned laser over a thin-film material enables heating and quench rates of up to 107 K/s. The development of a high-throughput variant, lateral gradient LSA, has recently been exploited to create time, temperature and composition maps of phase formation in a broad range of systems. Successful integration of this technique with active learning algorithms has further allowed autonomous searching, driving a new era of combinatorial high throughput materials discovery.While the autonomous searches can identify the ultimate structures formed, the evolution of the structure during LSA is difficult to study directly. Post-processing analysis of terminal structures can only infer transient changes that may be essential to understanding the kinetic behavior. In this work, we present a novel technique through which sub-millisecond materials transformations can be followed in situ during LSA, using the unique geometry of LSA to transform the time axis to a spatial dimension. Optical microscopy and X-ray diffraction are used to follow the sequences of metastable phase formation in situ for eleven oxide films as a function of both time and temperature, with time resolution down to 100 µs.Bi2O3, with a high oxygen ion conductivity in the δ-phase, is a polymorphic system of particular interest. Using in situ methods, we show that at high temperatures the δ-phase forms prior to melt and that at low temperatures the sputter-deposited amorphous precursor continually transforms to a two-phase region of δ + β due to the structural similarities between these phases and the low free energy cost of formation. In the Ga2o3 system, a widely studied ultra-wide bandgap semiconductor, we find that the defective-spinel γ-phase is the always first nucleating structure from as-deposited amorphous films, with a continuous solid-solid transformation to β occurring with increased temperatures. These results provide critical insight into the mechanisms determining the initial nucleating phase at high quench rates in oxide thin films.The ability to track and study the evolution of materials in situ provides a dramatic increase in the kinetic information accessible to researchers, which can be coupled with combinatorial and autonomous searches to more rapidly explore and understand metastable structures and their resultant properties.
- 일반주제명
- Materials science.
- 일반주제명
- Thermodynamics.
- 키워드
- Laser annealing
- 키워드
- Oxides
- 키워드
- Thin films
- 기타저자
- Cornell University Materials Science and Engineering
- 기본자료저록
- Dissertations Abstracts International. 85-03B.
- 기본자료저록
- Dissertation Abstract International
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
008240612s2023 us |||||||||||||||c||eng d■001000016934640
■00520240214101637
■006m o d
■007cr#unu||||||||
■020 ▼a9798380316903
■035 ▼a(MiAaPQ)AAI30631889
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a620.11
■1001 ▼aConnolly, Aine.▼0(orcid)0000-0002-2721-5621
■24510▼aMetastable Phase Formation and Materials Discovery in Complex Oxide Thin Films via Laser Spike Annealing▼h[electronic resource]
■260 ▼a[S.l.]:▼bCornell University. ▼c2023
■260 1▼aAnn Arbor :▼bProQuest Dissertations & Theses, ▼c2023
■300 ▼a1 online resource(152 p.)
■500 ▼aSource: Dissertations Abstracts International, Volume: 85-03, Section: B.
■500 ▼aAdvisor: Thompson, Michael O.
■5021 ▼aThesis (Ph.D.)--Cornell University, 2023.
■506 ▼aThis item must not be sold to any third party vendors.
■520 ▼aRapid thermal processing of materials, particularly processing techniques with high quench rates, have been demonstrated to form and stabilize ambient quenched non-equilibrium metastable phases. These phases often have distinct structures and properties, dramatically expanding the materials space available for applications. One such technique is Laser Spike Annealing (LSA), where a scanned laser over a thin-film material enables heating and quench rates of up to 107 K/s. The development of a high-throughput variant, lateral gradient LSA, has recently been exploited to create time, temperature and composition maps of phase formation in a broad range of systems. Successful integration of this technique with active learning algorithms has further allowed autonomous searching, driving a new era of combinatorial high throughput materials discovery.While the autonomous searches can identify the ultimate structures formed, the evolution of the structure during LSA is difficult to study directly. Post-processing analysis of terminal structures can only infer transient changes that may be essential to understanding the kinetic behavior. In this work, we present a novel technique through which sub-millisecond materials transformations can be followed in situ during LSA, using the unique geometry of LSA to transform the time axis to a spatial dimension. Optical microscopy and X-ray diffraction are used to follow the sequences of metastable phase formation in situ for eleven oxide films as a function of both time and temperature, with time resolution down to 100 µs.Bi2O3, with a high oxygen ion conductivity in the δ-phase, is a polymorphic system of particular interest. Using in situ methods, we show that at high temperatures the δ-phase forms prior to melt and that at low temperatures the sputter-deposited amorphous precursor continually transforms to a two-phase region of δ + β due to the structural similarities between these phases and the low free energy cost of formation. In the Ga2o3 system, a widely studied ultra-wide bandgap semiconductor, we find that the defective-spinel γ-phase is the always first nucleating structure from as-deposited amorphous films, with a continuous solid-solid transformation to β occurring with increased temperatures. These results provide critical insight into the mechanisms determining the initial nucleating phase at high quench rates in oxide thin films.The ability to track and study the evolution of materials in situ provides a dramatic increase in the kinetic information accessible to researchers, which can be coupled with combinatorial and autonomous searches to more rapidly explore and understand metastable structures and their resultant properties.
■590 ▼aSchool code: 0058.
■650 4▼aMaterials science.
■650 4▼aThermodynamics.
■653 ▼aLaser annealing
■653 ▼aMaterials discovery
■653 ▼aMetastable materials
■653 ▼aOxides
■653 ▼aThin films
■690 ▼a0794
■690 ▼a0348
■71020▼aCornell University▼bMaterials Science and Engineering.
■7730 ▼tDissertations Abstracts International▼g85-03B.
■773 ▼tDissertation Abstract International
■790 ▼a0058
■791 ▼aPh.D.
■792 ▼a2023
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T16934640▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
■980 ▼a202402▼f2024
