Over 50 years, Moore's law has successfully predicted the progress of the silicon electronics industry. However, Moore's law is approaching to the end recently, and new material and novel device type will be needed for next-generation devices. Two-dimensional (2D) layered material is one of the promising candidates due to its intrinsic desirable features, such as diverse electronic and magnetic properties, carrier mobility protection with decreasing body thickness, and flexibility for wearable applications. Furthermore, hetero-structure comprising of 2D crystals is of growing interest since various combinations are possible for multiple purposes as more and more van der Waals materials have been discovered. In a hetero-structure, electrons can propagate not only within 2D in-plane direction but also in the vertical out-of-plane direction. However, our understanding of the vertical carrier transport is greatly less than that on the lateral. Thus, using lateral electron energy band diagrams are still the main vehicle in 2D vertical hetero-structure device analysis, which may not be correct. In this dissertation, silicon-based tunneling devices were fabricated and used to investigate electron transport properties when electrons go into or go across a 2D materials with the measurement of electron tunneling spectroscopy. We firstly examine the role of 2D sheet when electrons propagate perpendicularly across it. Here graphene is used as a platform since it is the earliest discovered one, and it has the most mature development including understanding and growth techniques. Graphene together with its neighboring van de Waals gaps serves as a tunnel barrier and barely has interaction with the vertically tunneling electrons. However, since graphene can still trap a fraction of carriers, we can take advantage of it and control the carrier flux via the adjustment of graphene electrical potential. In addition to vertically propagating across a graphene sheet, electrons can go into graphene lateral band structure and transport within graphene. In chapter 3, we introduce a new model of the interfacial oscillation states at graphene-silicon hetero-junction, which is found and confirmed for the first time. Because of the presence of this discrete interfacial quantum state, Fano-Feshbach resonance is induced by its interaction with graphene's continuum lateral energy diagram. This study provided a further elucidation of the interfacial effect in a low-dimension materials based system. The capability of our silicon-based tunneling device along with electron tunneling spectroscopy is not limited to the graphene-silicon interface but also able to investigate electron in-plane transport behavior within 2D hetero-structure. Since large-size devices and their macroscopic characteristics would be needed for our everyday applications in the future, the strength of our tunneling device over the conventional scanning tunneling spectroscopy with a sharp tip is its scalable detecting area. Here, a study on graphene/hexagonal boron nitride hetero-stack prepared by chemical vapor deposition and large-area wet transfer techniques shows multiple secondary Dirac points and the preferred relative rotation angle of ~4 and ~7 . The theoretical calculation was also implemented to support our experimental observation. Raman spectroscopy and scanning tunneling microscope were carried out to confirm the Moire pattern formation. This study provides a useful way to macroscopically conduct research on the electronic behavior of a van der Waals material, and our findings may be used when graphene/hexagonal boron nitride hetero-structure is pushed to practical applications. Undoubtedly, further careful study is needed for more detailed verification.

Vertical integration of van der Waals (vdW) materials into heterostructures with atomic precision is one of the most intriguing possibilities brought forward by these 2-dimensional (2D) materials. Essential to the design and analysis of these structures is a fundamental understanding of the vertical transport of charge carriers into and across vdW materials. In this dissertation, I explore the important roles of single layer graphene in the vertical tunneling process, both as a collecting electrode and as a vdW tunneling barrier, and explore graphene's application as the base material of hot electron transistors (HETs). When graphene comes into contact with highly doped silicon, a fully preserved vdW gap is formed at the interface, which acts effectively as a tunnel barrier. In the scenario where graphene acts as the collecting electrodes, the electrons injected from the highly doped silicon are captured by graphene, and propagate laterally through graphene. Using electron tunneling spectroscopy (ETS), it is shown that this process is limited by the relaxation of carriers into the linear density of states of graphene. When graphene is sandwiched between two electrodes, the graphene layer together with the vdW gap act as a tunnel barrier that is transparent to the vertically tunneling electrons due to its atomic thickness and the mismatch of transverse momenta between the injected electrons and the graphene band structure. This is accentuated from the ETS showing a lack of features corresponding to the Dirac cone band structure of the graphene. Meanwhile, the graphene acts as a lateral conductor through which the potential and charge distribution across the tunnel barrier can be tuned. These unique properties make graphene an excellent 2D atomic net, which is transparent to charge carriers, and yet it can control the carrier flux via electrical potential at the same time. A new model including the effect of the quantum capacitance of the graphene for vertical tunneling is developed to further elucidate the role of graphene in modulating the tunneling process. As a result of the unique vertical transport properties of graphene, hot electron transistors with graphene as the base material and the vdW gap as the tunnel barrier can be fabricated, eliminating the need for an additional tunnel barrier. This leads to significantly increased current densities, as well as minimized energy loss for the hot electrons in the tunnel barrier, which in turn leads to lower turn on voltages and higher current gain, compared to previous reports of graphene based HETs.

21st Century Nanoscience - A Handbook: Nanophotonics, Nanoelectronics, and Nanoplasmonics (Volume 6) will be the most comprehensive, up-to-date large reference work for the field of nanoscience. Handbook of Nanophysics by the same editor published in the fall of 2010 and was embraced as the first comprehensive reference to consider both fundamental and applied aspects of nanophysics. This follow-up project has been conceived as a necessary expansion and full update that considers the significant advances made in the field since 2010. It goes well beyond the physics as warranted by recent developments in the field. This sixth volume in a ten-volume set covers nanophotonics, nanoelectronics, and nanoplasmonics. Key Features: Provides the most comprehensive, up-to-date large reference work for the field. Chapters written by international experts in the field. Emphasises presentation and real results and applications. This handbook distinguishes itself from other works by its breadth of coverage, readability and timely topics. The intended readership is very broad, from students and instructors to engineers, physicists, chemists, biologists, biomedical researchers, industry professionals, governmental scientists, and others whose work is impacted by nanotechnology. It will be an indispensable resource in academic, government, and industry libraries worldwide. The fields impacted by nanophysics extend from materials science and engineering to biotechnology, biomedical engineering, medicine, electrical engineering, pharmaceutical science, computer technology, aerospace engineering, mechanical engineering, food science, and beyond.

Semiconductor nanostructures are ideal systems to tailor the physical properties via quantum effects, utilizing special growth techniques, self-assembling, wet chemical processes or lithographic tools in combination with tuneable external electric and magnetic fields. Such systems are called "Quantum Materials".The electronic, photonic, and phononic properties of these systems are governed by size quantization and discrete energy levels. The charging is controlled by the Coulomb blockade. The spin can be manipulated by the geometrical structure, external gates and by integrating hybrid ferromagnetic emitters.This book reviews sophisticated preparation methods for quantum materials based on III-V and II-VI semiconductors and a wide variety of experimental techniques for the investigation of these interesting systems. It highlights selected experiments and theoretical concepts and gives such a state-of-the-art overview about the wide field of physics and chemistry that can be studied in these systems.

Nanostructured materials is one of the hottest and fastest growing areas in today's materials science field, along with the related field of solid state physics. Nanostructured materials and their based technologies have opened up exciting new possibilites for future applications in a number of areas including aerospace, automotive, x-ray technology, batteries, sensors, color imaging, printing, computer chips, medical implants, pharmacy, and cosmetics. The ability to change properties on the atomic level promises a revolution in many realms of science and technology. Thus, this book details the high level of activity and significant findings are available for those involved in research and development in the field. It also covers industrial findings and corporate support. This five-volume set summarizes fundamentals of nano-science in a comprehensive way. The contributors enlisted by the editor are at elite institutions worldwide. Key Features * Provides comprehensive coverage of the dominant technology of the 21st century * Written by 127 authors from 16 countries, making this truly international * First and only reference to cover all aspects of nanostructured materials and nanotechnology

This volume contains a sequence of reviews presented at the NATO Advanced Study Institute on 'Low Dimensional Structures in Semiconductors ... from Basic Physics to Applications.' This was part of the International School of Materials Science and 1990 at the Ettore Majorana Centre in Sicily. Technology held in July Only a few years ago, Low Dimensional Structures was an esoteric concept, but now it is apparent they are likely to playa major role in the next generation of electronic devices. The theme of the School acknowledged this rapidly developing maturity.' The contributions to the volume consider not only the essential physics, but take a wider view of the topic, starting from material growth and processing, then prog ressing right through to applications with some discussion of the likely use of low dimensional devices in systems. The papers are arranged into four sections, the first of which deals with basic con cepts of semiconductor and low dimensional systems. The second section is on growth and fabrication, reviewing MBE and MOVPE methods and discussing the achievements and limitations of techniques to reduce structures into the realms of one and zero dimensions. The third section covers the crucial issue of interfaces while the final section deals with devices and device physics.

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

This textbook is aimed at second-year graduate students in Physics, Electrical Engineering, or Materials Science. It presents a rigorous introduction to electronic transport in solids, especially at the nanometer scale.Understanding electronic transport in solids requires some basic knowledge of Hamiltonian Classical Mechanics, Quantum Mechanics, Condensed Matter Theory, and Statistical Mechanics. Hence, this book discusses those sub-topics which are required to deal with electronic transport in a single, self-contained course. This will be useful for students who intend to work in academia or the nano/ micro-electronics industry.Further topics covered include: the theory of energy bands in crystals, of second quantization and elementary excitations in solids, of the dielectric properties of semiconductors with an emphasis on dielectric screening and coupled interfacial modes, of electron scattering with phonons, plasmons, electrons and photons, of the derivation of transport equations in semiconductors and semiconductor nanostructures somewhat at the quantum level, but mainly at the semi-classical level. The text presents examples relevant to current research, thus not only about Si, but also about III-V compound semiconductors, nanowires, graphene and graphene nanoribbons. In particular, the text gives major emphasis to plane-wave methods applied to the electronic structure of solids, both DFT and empirical pseudopotentials, always paying attention to their effects on electronic transport and its numerical treatment. The core of the text is electronic transport, with ample discussions of the transport equations derived both in the quantum picture (the Liouville-von Neumann equation) and semi-classically (the Boltzmann transport equation, BTE). An advanced chapter, Chapter 18, is strictly related to the ‘tricky’ transition from the time-reversible Liouville-von Neumann equation to the time-irreversible Green’s functions, to the density-matrix formalism and, classically, to the Boltzmann transport equation. Finally, several methods for solving the BTE are also reviewed, including the method of moments, iterative methods, direct matrix inversion, Cellular Automata and Monte Carlo. Four appendices complete the text.

This book is a printed edition of the Special Issue "Integration of 2D Materials for Electronics Applications" that was published in Crystals