Fabrication of In-situ MgB2 Thin Films on Al2O3 Substrate Using Off-axis PLD Technique

Fabrication of In-situ MgB2 Thin Films on Al2O3 Substrate Using Off-axis PLD Technique PDF Author: Yi Sun Wu
Publisher:
ISBN:
Category : Annealing of metals
Languages : en
Pages : 134

Get Book Here

Book Description

Fabrication of In-situ MgB2 Thin Films on Al2O3 Substrate Using Off-axis PLD Technique

Fabrication of In-situ MgB2 Thin Films on Al2O3 Substrate Using Off-axis PLD Technique PDF Author: Yi Sun Wu
Publisher:
ISBN:
Category : Annealing of metals
Languages : en
Pages : 134

Get Book Here

Book Description


Fabrication and Characterization of Superconducting PLD MgB2 Thin Films

Fabrication and Characterization of Superconducting PLD MgB2 Thin Films PDF Author: Yue Zhao
Publisher:
ISBN:
Category : Magnesium compounds
Languages : en
Pages : 394

Get Book Here

Book Description


Fabrication of Thin Films by Pulsed Laser Deposition for Clean Energy Applications

Fabrication of Thin Films by Pulsed Laser Deposition for Clean Energy Applications PDF Author: Xiaojun Zhang
Publisher:
ISBN:
Category :
Languages : en
Pages : 79

Get Book Here

Book Description
Pulsed laser deposition (PLD) is a physical vapor deposition technique for thin film fabrication. Compared with other techniques, pulsed laser deposition technique has advantages such as stoichiometry, flexibility, versatility, lower deposition temperature, ability to grow metastable materials. Because of these advantages, pulsed laser deposition has been widely used in materials research. In this dissertation, pulsed laser deposition has been used to grow thin films for solid oxide fuel cell, light-emitting diode, and solar cell applications. Firstly, yttria-stabilized zirconia (YSZ) and cerium dioxide (CeO2) thin films are deposited in oxygen-deficient environments; their properties are compared to those deposited in oxygen-rich environments. Oxygen-deficient films are highly (001)-oriented, which corresponds to a surface that is expected to be forbidden based on Tasker's theoretical calculation of stoichiometric ionic crystals. A model considering non-stoichiometry-induced surface relaxation and surface atomic density is proposed to explain the orientation phenomenon observed under oxygen-deficient deposition conditions. This model is consistent with previous experimental results for indium tin oxide (ITO), SnO2 and NiO thin films deposited under similar conditions. Detailed studies of the preferred orientation of these oxygen-deficient ionic crystals are of direct relevance to the fabrication of films for use in solid oxide fuel cells. Secondly, undoped, Cu-doped, Se-enriched, Cu2Se-doped, Ag-doped, Ag2Se-doped, and nitrogen-doped ZnSe films have been grown on fused quartz substrates by pulsed laser deposition. It is found that adding a small amount (~2 mol%) of Cu2Se can significantly improve crystallinity and (111) texturing of ZnSe films. While the other films are highly resistive, Cu2Se-doped ZnSe films are p-type conducting with hole concentrations of ~ cm-3 and resistivity of ~0.098 ohm*cm (compared with previous reports of ~ cm-3 and 0.75 ohm*cm, respectively). The successful heavy p-type doping of ZnSe films is attributed to substitution of Zn atoms with Cu while limiting selenium-vacancy-associated compensating defects with additional selenium. Nitrogen doping has turned ZnSe films more favorable to wurtzite structures. Two newly observed Raman peaks at 555 cm-1 and 602 cm-1 are assigned to N local vibrational modes of hexagonal ZnSe structures. The nitrogen-doped ZnSe films are not conductive, which might be due to compensating defects arising from the presence of native defects or other impurities. This work is of importance to solve doping difficulties and contact problems of wide-bandgap semiconductors. Finally, batch growth of thin films by pulsed laser deposition has been tried. Using the natural temperature gradient, films with different deposition temperatures have been fabricated together. With change of deposition temperatures, ZnSe films are shown to have problems associated with crystalline defects, selenium loss, or phase separation. ZnSe films with improved crystallinity and no phase separation have been achieved using a 16 mol% Se enriched target. Multi-plume pulsed laser deposition has been proposed and discussed. With directionality of PLD plumes and non-uniformity of PLD films, this system is supposed to be more suitable for high-throughput compound thin film fabrication, which makes it very promising for efficient materials optimization and exploration. High-throughput fabrication of compound thin films has been successfully achieved using this system.

Spectroscopy of Complex Oxide Interfaces

Spectroscopy of Complex Oxide Interfaces PDF Author: Claudia Cancellieri
Publisher: Springer
ISBN: 3319749897
Category : Technology & Engineering
Languages : en
Pages : 326

Get Book Here

Book Description
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.

Handbook of Superconducting Materials

Handbook of Superconducting Materials PDF Author: David A. Cardwell
Publisher: CRC Press
ISBN: 9780750308977
Category : Medical
Languages : en
Pages : 1136

Get Book Here

Book Description


Hard X-ray Photoelectron Spectroscopy (HAXPES)

Hard X-ray Photoelectron Spectroscopy (HAXPES) PDF Author: Joseph Woicik
Publisher: Springer
ISBN: 3319240439
Category : Science
Languages : en
Pages : 576

Get Book Here

Book Description
This book provides the first complete and up-to-date summary of the state of the art in HAXPES and motivates readers to harness its powerful capabilities in their own research. The chapters are written by experts. They include historical work, modern instrumentation, theory and applications. This book spans from physics to chemistry and materials science and engineering. In consideration of the rapid development of the technique, several chapters include highlights illustrating future opportunities as well.

Crystal Growth Technology

Crystal Growth Technology PDF Author: Hans J. Scheel
Publisher: John Wiley & Sons
ISBN: 0470491108
Category : Science
Languages : en
Pages : 695

Get Book Here

Book Description
This volume deals with the technologies of crystal fabrication, of crystal machining, and of epilayer production and is the first book on industrial and scientific aspects of crystal and layer production. The major industrial crystals are treated: Si, GaAs, GaP, InP, CdTe, sapphire, oxide and halide scintillator crystals, crystals for optical, piezoelectric and microwave applications and more. Contains 29 contributions from leading crystal technologists covering the following topics: * General aspects of crystal growth technology * Silicon * Compound semiconductors * Oxides and halides * Crystal machining * Epitaxy and layer deposition Scientific and technological problems of production and machining of industrial crystals are discussed by top experts, most of them from the major growth industries and crystal growth centers. In addition, it will be useful for the users of crystals, for teachers and graduate students in materials sciences, in electronic and other functional materials, chemical and metallurgical engineering, micro-and optoelectronics including nanotechnology, mechanical engineering and precision-machining, microtechnology, and in solid-state sciences.

Photoelectron Spectroscopy

Photoelectron Spectroscopy PDF Author: Shigemasa Suga
Publisher: Springer
ISBN: 3642375308
Category : Science
Languages : en
Pages : 389

Get Book Here

Book Description
Photoelectron spectroscopy is now becoming more and more required to investigate electronic structures of various solid materials in the bulk, on surfaces as well as at buried interfaces. The energy resolution was much improved in the last decade down to 1 meV in the low photon energy region. Now this technique is available from a few eV up to 10 keV by use of lasers, electron cyclotron resonance lamps in addition to synchrotron radiation and X-ray tubes. High resolution angle resolved photoelectron spectroscopy (ARPES) is now widely applied to band mapping of materials. It attracts a wide attention from both fundamental science and material engineering. Studies of the dynamics of excited states are feasible by time of flight spectroscopy with fully utilizing the pulse structures of synchrotron radiation as well as lasers including the free electron lasers (FEL). Spin resolved studies also made dramatic progress by using higher efficiency spin detectors and two dimensional spin detectors. Polarization dependent measurements in the whole photon energy spectrum of the spectra provide useful information on the symmetry of orbitals. The book deals with the fundamental concepts and approaches for the application of this technique to materials studies. Complementary techniques such as inverse photoemission, photoelectron diffraction, photon spectroscopy including infrared and X-ray and scanning tunneling spectroscopy are presented. This book provides not only a wide scope of photoelectron spectroscopy of solids but also extends our understanding of electronic structures beyond photoelectron spectroscopy.

Applications of Superconductivity

Applications of Superconductivity PDF Author: H. Weinstock
Publisher: Springer Science & Business Media
ISBN: 9401707529
Category : Technology & Engineering
Languages : en
Pages : 695

Get Book Here

Book Description
This book, in essence the proceedings of a NATO Advanced Study Institute with the same title, is designed to provide in-depth coverage of many, but not all, of the major current applications of superconductivity, and of many that still are being developed. It will be of value to scientists and engineers who have interests in the research and production aspects of the technology, as well as in the applications themselves. The ftrst three chapters (by Clarke, Vrba and Wikswo) are devoted to an understanding of the principles, fabrication and uses of SQUID magnetometers and gradiometers, with the greatest emphasis on biomagnetism and nondestructive evaluation (NDE). For the most part, traditional low-temperature superconductor (LTS) SQUIDs are used, but particularly for NDE, high-temperature superconductor (HTS) SQUIDs are proving useful and often more convenient. The succeeding three chapters (by Przybysz, Likharev and Chaloupka) cover broader aspects of superconducting electronics. The ftrst two of these deal primarily with digital L TS circuits, while the third discusses in great detail passive component applications using HTS materials. Currently, HTS ftlters are undergoing intense J3-site testing at cellular telephone base stations. While it is clear that HTS ftlters outperform conventional ftlters in reducing signal loss and allowing for more channels in a given bandwidth, it isn't yet certain that the cellular telephone industry sees sufficient economic beneftts to make a ftrm decision to use HTS ftlters universally in its systems. If this application is generally adapted, the market for these ftlters should be quite large.

Superconductivity

Superconductivity PDF Author: Paolo Mele
Publisher: Springer Nature
ISBN: 3030233030
Category : Technology & Engineering
Languages : en
Pages : 369

Get Book Here

Book Description
This book provides readers with a comprehensive overview of the science of superconducting materials. It serves as a fundamental information source on the actual techniques and methodologies involved in superconducting materials growth, characterization and processing. This book includes coverage of several categories of medium and high-temperature superconducting materials: cuprate oxides, borides, and iron-based chalcogenides and pnictides. Provides a single-source reference on superconducting materials growth, characterization and processing; Bridges the gap between materials science and applications of superconductors; Discusses several categories of superconducting materials such as cuprate oxides, borides, and iron-based chalcogenides and pnictides; Covers synthesis, characterization, and processing of superconducting materials, as well as the nanoengineering approach to tailor the properties of the used materials at the nanoscale level.