Download or read book Theoretical Investigation of Oxide semiconductor Interfaces written by Donghan Shin and published by . This book was released on 2019 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Functional oxides and their heterostructures have been investigated in condensed matter physics for decades since they exhibit many emergent phenomena. In particular, oxide/semiconductor interfaces have been extensively studied and have significantly impacted both industry and academia due to their wide range of physical phenomena. In this dissertation, I theoretically investigate two systems: graphene/STO and rare-earth oxide/GaN interfaces. For the first system, I consider theoretically, the possibility of electrostatic doping of graphene by the intrinsic field of a polar substrate. By way of example, I perform density functional theory calculations for a graphene sheet placed on the (111)-oriented perovskite SrTiO3 surface. I find that the Fermi surface shifts well below the Dirac point of graphene, resulting simultaneously in a fast conducting channel in graphene, and a slow (large-effective-mass) channel at the oxide surface. Moreover, further theoretical analysis suggests that coupling of electrons in graphene to interfacial hybrid plasmon/optical modes may result in an effectively attractive electron-electron interaction that, in turn, could result in electron pairing and lead to superconductivity. In this analysis I consider remote optical phonon scattering in graphene on STO and find that the attractive electron-remote phonon interaction is much larger than the repulsive Coulomb interaction, resulting effectively in an attractive interaction. For the second system, I investigate the electronic structures of bare (0001)-oriented surface of wurzite GaN and rare-earth (RE) Ce, Eu, and Gd ad-atoms on it. I also explore the possibility of forming a Zintl-like transition layer, EuGa2. When a Eu atom is placed on the surface, there is charge transfer between Eu and Ga, resulting in a geometrical change and formation of bonding between Eu and Ga. The bond length is comparable with the bond length of EuGa2, which is a Zintl-like intermetallic compound. This charge transfer is also studied by Bader charge and model Hamiltonian analysis. In addition I calculated the electronic structure of bulk Eu2O3 and its slab to estimate the band alignment between Eu2O3 and GaN

Download or read book Chemical Dynamics and Bonding at Gas semiconductor and Oxide semiconductor Interfaces written by Sarah R. Bishop and published by . This book was released on 2010 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas and oxide adsorption and their impact on the properties of semiconductor interfaces were investigated at the atomic level with both experimental and theoretical techniques. Two types of semiconductors were studied, an organic semiconductor, employed in chemical field effect transistors (chemFETs) and alternative channel materials for metal oxide field effect transistors (MOSFETs). Adsorption of nitric oxide (NO) on iron phthalocyanine (FePc), an organic semiconductor, was explored to determine the adsorption mechanism of NO. King and Wells sticking measurements were performed on ordered monolayer, multilayer FePc and quasi-amorphous tetra-t-butyl FePc multilayer thin films to determine the impact of surface order and thickness on adsorption. Density functional theory (DFT) results show there is a deep chemisorption well at the metal center. The metal centers are a small fraction of the surface (3%), but the initial sticking probability was 40% at low surface temperature and low incident beam energy. Both the experimental and theoretical data supports molecular NO sticking onto FePc via physisorption to the aromatic periphery followed by diffusion to the Fe metal center, a multiple pathway precursor-mediated chemisorption. To understand the chemical dynamics of bonding at the oxide/semiconductor interface, the adsorption of oxygen, nitrogen, and high-[kappa] dielectrics onto alternative high mobility channel materials, Ge and InAs, was investigated to identify passive oxide/semiconductor interfaces via DFT. DFT modeling of experimental results found oxygen exposure on Ge(0 0 1)-(4 x 2) pins the Fermi level near the valence band due to generation of Ge ad-atoms and formation of a suboxide. Similarly, DFT modeling demonstrated that the nitrided Ge(001) surface was pinned due to generation of Ge ad-atoms and formation of a subnitride. For III-V materials, a comparison was made of the geometric and electronic structures of ordered HfO2 and ZrO2 monolayers on InAs(0 0 1)-(4 x 2). DFT calculations showed that both high-k oxides were able to electronically passivate the InAs(0 0 1)-(4 x 2) surface, decreasing density of states at the Fermi level by removal of dangling bonds and strained bonds on the semiconductor substrate. With a greater atomic understanding of the oxide-semiconductor interfaces, the presented results can help guide future device engineering efforts.

Download or read book Spectroscopy of Complex Oxide Interfaces written by Claudia Cancellieri and published by Springer. This book was released on 2018-04-09 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the most recent and compelling experimental results for complex oxide interfaces. The results of this book were obtained with the cutting-edge photoemission technique at highest energy resolution. Due to their fascinating properties for new-generation electronic devices and the challenge of investigating buried regions, the book chiefly focuses on complex oxide interfaces. The crucial feature of exploring buried interfaces is the use of soft X-ray angle-resolved photoemission spectroscopy (ARPES) operating on the energy range of a few hundred eV to increase the photoelectron mean free path, enabling the photons to penetrate through the top layers – in contrast to conventional ultraviolet (UV)-ARPES techniques. The results presented here, achieved by different research groups around the world, are summarized in a clearly structured way and discussed in comparison with other photoemission spectroscopy techniques and other oxide materials. They are complemented and supported by the most recent theoretical calculations as well as results of complementary experimental techniques including electron transport and inelastic resonant X-ray scattering.

Download or read book Theoretical Investigation of III V and Metal Oxide Compounds written by Fatima F. Al-Quaiti and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Invented in 1947, the transistor quickly became an integral component of electronic devices. An every-increasing demand for more powerful, compact, and versatile electronics has driven research for materials to meet this demand. These materials include large band gap semiconductors with higher breakdown voltages and power capacities and semiconductors that can tolerate high-temperature or physiological environments. The work presented here covers a study on GaN, a wide band gap semiconductor with applications in high-frequency, high-temperature, and high-power electronics. We study the surface properties of the GaN surface under N- and Ga-rich conditions and the interaction of La and Ga ad-atoms with the GaN surface. We found the diffusion of the ad-atoms is directionally dependent and that it is energetically favorable for the La ad-atom to exchange positions with a surface Ga atom and form LaN. Along the same lines as GaN, we investigate the properties of Ga2O3, which also has potential in high-power electronics. The last semiconductor we consider is In2O3, which has potential for use in highly sensitive sensors. The search for alternative materials for transistors includes insulators with a high dielectric constant, such as La2O3. Here, we present a study on the bulk and surface properties of the ground state and metastable phases of Ga2O3, In2O3, and La2O3. Our aim in this study is to better understand the reason behind the appearance of metastable phases and higher energy surface terminations during crystal growth. Another body research focuses on studying designing devices that can replace traditional transistors altogether. One such example is a logic device based on a phase change material (PCM), which possesses stable amorphous and crystalline states which have significant differences in their optical and electronic properties. Here we present a study on Sb and GaSb, two PCMs with great potential for use in the next generation of PCM-based memory devices due to their reduced chemical complexity and low mass density change between the amorphous and crystalline phases. In this study, we investigate the structural and elastic properties of Sb and GaSb and find that phase separation arises in the amorphous phase as the Ga content increases

Download or read book A Theoretical Study of Oxide Defects Near a Silicon silicon Dioxide Interface written by Andrew Xun Chu and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamentals of Novel Oxide semiconductor Interfaces written by C. R. Abernathy and published by . This book was released on 2004 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Research in Progress written by and published by . This book was released on with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Field Effect in Semiconductor Electrolyte Interfaces written by Pavel P. Konorov and published by Princeton University Press. This book was released on 2021-01-12 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a state-of-the-art understanding of semiconductor-electrolyte interfaces. It provides a detailed study of semiconductor-electrolyte interfacial effects, focusing on the physical and electrochemical foundations that affect surface charge, capacitance, conductance, quantum effects, and other properties, both from the point of view of theoretical modeling and metrology. The wet-dry interface, where solid-state devices may be in contact with electrolyte solutions, is of growing interest and importance. This is because such interfaces will be a key part of hydrogen energy and solar cells, and of sensors that would have wide applications in medicine, genomics, environmental science, and bioterrorism prevention. The field effect presented here by Pavel Konorov, Adil Yafyasov, and Vladislav Bogevolnov is a new method, one that allows investigation of the physical properties of semiconductor and superconductor surfaces. Before the development of this method, it was impossible to test these surfaces at room temperature. The behavior of electrodes in electrolytes under such realistic conduction conditions has been a major problem for the technical realization of systems that perform measurements in wet environments. This book also describes some material properties that were unknown before the development of the field effect method. This book will be of great interest to students and engineers working in semiconductor surface physics, electrochemistry, and micro- and nanoelectronics.

Download or read book Postdoctoral Research Associateships written by and published by . This book was released on 1986 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Semiconductor Surfaces and Interfaces written by Winfried Mönch and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: This third edition has been thoroughly revised and updated. In particular it now includes an extensive discussion of the band lineup at semiconductor interfaces. The unifying concept is the continuum of interface-induced gap states.

Download or read book Theoretical Investigation of Electron States in Small scale Semiconductor Structures written by Christian Mailhiot and published by . This book was released on 1984 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theoretical Investigations of Complex Oxides written by Valentino R. Cooper and published by . This book was released on 2005 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Research in Progress Between and written by United States. Army Research Office and published by . This book was released on 1978 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book OAR written by and published by . This book was released on 1967 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Springer Handbook of Inorganic Photochemistry written by Detlef Bahnemann and published by Springer Nature. This book was released on 2022-06-25 with total page 1914 pages. Available in PDF, EPUB and Kindle. Book excerpt: The handbook comprehensively covers the field of inorganic photochemistry from the fundamentals to the main applications. The first section of the book describes the historical development of inorganic photochemistry, along with the fundamentals related to this multidisciplinary scientific field. The main experimental techniques employed in state-of-art studies are described in detail in the second section followed by a third section including theoretical investigations in the field. In the next three sections, the photophysical and photochemical properties of coordination compounds, supramolecular systems and inorganic semiconductors are summarized by experts on these materials. Finally, the application of photoactive inorganic compounds in key sectors of our society is highlighted. The sections cover applications in bioimaging and sensing, drug delivery and cancer therapy, solar energy conversion to electricity and fuels, organic synthesis, environmental remediation and optoelectronics among others. The chapters provide a concise overview of the main achievements in the recent years and highlight the challenges for future research. This handbook offers a unique compilation for practitioners of inorganic photochemistry in both industry and academia.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Integration of Functional Oxides with Semiconductors written by Alexander A. Demkov and published by Springer Science & Business Media. This book was released on 2014-02-20 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the basic physical principles of the oxide/semiconductor epitaxy and offers a view of the current state of the field. It shows how this technology enables large-scale integration of oxide electronic and photonic devices and describes possible hybrid semiconductor/oxide systems. The book incorporates both theoretical and experimental advances to explore the heteroepitaxy of tuned functional oxides and semiconductors to identify material, device and characterization challenges and to present the incredible potential in the realization of multifunctional devices and monolithic integration of materials and devices. Intended for a multidisciplined audience, Integration of Functional Oxides with Semiconductors describes processing techniques that enable atomic-level control of stoichiometry and structure and reviews characterization techniques for films, interfaces and device performance parameters. Fundamental challenges involved in joining covalent and ionic systems, chemical interactions at interfaces, multi-element materials that are sensitive to atomic-level compositional and structural changes are discussed in the context of the latest literature. Magnetic, ferroelectric and piezoelectric materials and the coupling between them will also be discussed. GaN, SiC, Si, GaAs and Ge semiconductors are covered within the context of optimizing next-generation device performance for monolithic device processing.