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Phase and Defect Control of 2D-Material Based Memory Devices by Scanning Tunneling Microscopy
Phase and Defect Control of 2D-Material Based Memory Devices by Scanning Tunneling Microscopy
상세정보
- 자료유형
- 학위논문 서양
- 최종처리일시
- 20260311091536.5
- ISBN
- 9798270232139
- DDC
- 621.3815
- 서명/저자
- Phase and Defect Control of 2D-Material Based Memory Devices by Scanning Tunneling Microscopy / Nicholas Domingo Ignacio
- 발행사항
- [Sl] : The University of Texas at Austin, 2025
- 형태사항
- 1 electronic resource (109 pages)
- 주기사항
- Source: Dissertations Abstracts International, Volume: 87-06, Section: B.
- 주기사항
- Advisors: Akinwande, Deji Committee members: Warner, Jamie; Lai, Keji; Banerjee, Sanjay.
- 학위논문주기
- - Ph.D. : The University of Texas at Austin, 2025.
- 초록/해제
- 요약In recent years, two-dimensional (2D) van der Waals (vdW) materials have aroused much interest for their unique structural, thermal, optical, and electronic properties and have become a hot topic in condensed matter physics and material science. Many research methods, including scanning tunneling microscopy (STM), transmission electron microscopy (TEM), optical and transport measurements, have been used to investigate these unique properties. Among them, STM stands out as a powerful characterization tool with atomic resolution and is capable of simultaneously revealing both atomic structures and local electronic properties. In this thesis, I will describe scanning tunneling microscopy experiments which probe the mechanisms which drive select 2D material-based resistive switching technologies.Chapter 1 is an introduction to 2D materials and the resistive switching memories discussed in this dissertation. In Chapter 2, I will provide the basic principles of STM and a description of the types of measurements that enabled much of this work. I will then present studies on the phase control of In2Se3 and the resulting applications to phase change memory. First in Chapter 3, the preservation of β-phase In2Se3 via limitation of an oxidative environment first noticed in STM is presented. Work on the engineering of the phase transformation of In2Se3 is expanded upon in Chapter 4 where we show the transition between α- In2Se3 and β- In2Se3 can be triggered via electrical excitation from the STM tip. We unveil the vertical propagation of the phase change across the van der Waals gaps of both layered In2Se3 phases that can be controlled by the switching current delivered by the STM tip allowing for layer-by-layer switching that unlocks multi-state PCM. Chapters 5 and 6 focus on hBN based devices. The impact of electrode topography and defects in a silver/monolayer-hBN/silver memristor is studied via STM and an analysis of defect density in monolayer hBN grown via CVD is presented in Chapter 5. Finally, I present an observation of Random Telegraph Noise (RTN) in monolayer hBN through direct electrical measurements of single-point vacancies via STM. We show the dependence of defects for this characterization and provide a comprehensive study of the stochastic phenomena examining the effects of electrode material, temperature, and constant voltage stress on the RTN signal. This work vastly improves the spatial resolution of which RTN has been observed and presents a RTN with ultralow current and high current fluctuations critical for implementation in encryption systems.
- 언어주기
- English
- 일반주제명
- Quantum physics
- 일반주제명
- Materials science
- 일반주제명
- Nanoscience
- 기타저자
- The University of Texas at Austin Materials Science and Engineering
- 기본자료저록
- Dissertations Abstracts International. 87-06B.
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
008260311s2025 us eng d■001000017361210
■00520260311091536.5
■006m o d
■007cr|nu||||||||
■020 ▼a9798270232139
■040 ▼aMiAaPQD▼beng▼cMiAaPQD▼erda
■082 ▼a621.3815
■1001 ▼aIgnacio, Nicholas Domingo▼eauthor.
■24510▼aPhase and Defect Control of 2D-Material Based Memory Devices by Scanning Tunneling Microscopy ▼cNicholas Domingo Ignacio
■260 ▼a[Sl]▼bThe University of Texas at Austin▼c2025
■264 1▼aAnn Arbor▼bProQuest Dissertations & Theses▼c2025
■300 ▼a1 electronic resource (109 pages)
■336 ▼atext▼btxt▼2rdacontent
■337 ▼acomputer▼bc▼2rdamedia
■338 ▼aonline resource▼bcr▼2rdacarrier
■500 ▼aSource: Dissertations Abstracts International, Volume: 87-06, Section: B.
■500 ▼aAdvisors: Akinwande, Deji Committee members: Warner, Jamie; Lai, Keji; Banerjee, Sanjay.
■5021 ▼bPh.D.▼cThe University of Texas at Austin▼d2025.
■520 ▼aIn recent years, two-dimensional (2D) van der Waals (vdW) materials have aroused much interest for their unique structural, thermal, optical, and electronic properties and have become a hot topic in condensed matter physics and material science. Many research methods, including scanning tunneling microscopy (STM), transmission electron microscopy (TEM), optical and transport measurements, have been used to investigate these unique properties. Among them, STM stands out as a powerful characterization tool with atomic resolution and is capable of simultaneously revealing both atomic structures and local electronic properties. In this thesis, I will describe scanning tunneling microscopy experiments which probe the mechanisms which drive select 2D material-based resistive switching technologies.Chapter 1 is an introduction to 2D materials and the resistive switching memories discussed in this dissertation. In Chapter 2, I will provide the basic principles of STM and a description of the types of measurements that enabled much of this work. I will then present studies on the phase control of In2Se3 and the resulting applications to phase change memory. First in Chapter 3, the preservation of β-phase In2Se3 via limitation of an oxidative environment first noticed in STM is presented. Work on the engineering of the phase transformation of In2Se3 is expanded upon in Chapter 4 where we show the transition between α- In2Se3 and β- In2Se3 can be triggered via electrical excitation from the STM tip. We unveil the vertical propagation of the phase change across the van der Waals gaps of both layered In2Se3 phases that can be controlled by the switching current delivered by the STM tip allowing for layer-by-layer switching that unlocks multi-state PCM. Chapters 5 and 6 focus on hBN based devices. The impact of electrode topography and defects in a silver/monolayer-hBN/silver memristor is studied via STM and an analysis of defect density in monolayer hBN grown via CVD is presented in Chapter 5. Finally, I present an observation of Random Telegraph Noise (RTN) in monolayer hBN through direct electrical measurements of single-point vacancies via STM. We show the dependence of defects for this characterization and provide a comprehensive study of the stochastic phenomena examining the effects of electrode material, temperature, and constant voltage stress on the RTN signal. This work vastly improves the spatial resolution of which RTN has been observed and presents a RTN with ultralow current and high current fluctuations critical for implementation in encryption systems.
■546 ▼aEnglish
■590 ▼aSchool code: 0227
■650 4▼aQuantum physics
■650 4▼aMaterials science
■650 4▼aNanoscience
■653 ▼aTransmission electron microscopy
■653 ▼aScanning tunneling microscopy
■653 ▼aTransport measurements
■653 ▼aRandom Telegraph Noise
■7102 ▼aThe University of Texas at Austin▼bMaterials Science and Engineering.▼edegree granting institution.
■7201 ▼aAkinwande, Deji▼edegree supervisor.
■7730 ▼tDissertations Abstracts International▼g87-06B.
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T17361210▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
