Download or read book MBE Growth and Characterization of Zincblende GaN and GaN AlN Structures written by J. Song and published by . This book was released on 1997 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Program includes fundamental studies of Molecular beam epitaxial (MBE) growth of GaN and its related alloys and heterostructures. In additions, the optical and electrical properties of resultant materials were measured using a variety of spectroscopic techniques. The optical properties concentrated on optically-pumped stimulated emission and laser action in GaN/AlGaN heterostructures. The objective was to better understand the underlying physics of MBE growth, and the optical and electrical properties for GaN-based device application. 1.
Download or read book MBE Growth and Characterization of GaN AlN Structures Under Hydrostatic Pressure written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the results of a series of studies on the optical properties of GaN and AlGaN/GaN heterostructures using a variety of spectroscopic techniques. Strain effects were found to have a strong influence in determining the energies of excitonic transitions. The observations of spectral features associated with the transitions involving the ground and excited exciton states make it possible to directly estimate binding energy for the excitons in GaN. Optical pumping experiments were performed on AlGaN/GaN separate confinement heterostructures (SCH) grown on sapphire by MBE and SiC by MOCVD. The threshold pumping powers were found to be an order of magnitude lowere than that for regular GaN epilayers. Nonlinear four-wave-mixing experiments were carried out in both femtosecond and picosecond regimes to study the intensity and time response of scattering efficiency, as well as the pump-induced nonlinear refractive index change.
Download or read book GaN AlN Multiple Quantum Well Structures written by Xinyu Liu and published by . This book was released on 2007 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MBE Growth and Characterization of GaN AlN Structure Under Hydrostatic Pressure written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the results of a series of studies on the optical properties of GaN and AlGaN/GaN heterostructure using a variety of spectroscopic techniques. Strain effects were found to have a strong influence in determining the energies of excitonic transitions. The observations of spectral features associated with the transitions involving the ground and excited exciton states make it possible to directly estimate binding energy for the excitons in GaN. Optical pumping experiments were performed on AlGaN/GaN separate confinement heterostructures (SCH) grown on sapphire by MBE and SiC by MOCVD. The threshold pumping powers were found to be an order of magnitude lower than that for regular GaN epilayers. Nonlinear four wave mixing experiments were carried out in both femtosecond and picosecond regimes to study the intensity and time response of scattering efficiency, as well as the pump induced nonlinear refractive index change.
Download or read book Molecular Beam Epitaxy written by Mohamed Henini and published by Elsevier. This book was released on 2018-06-27 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular Beam Epitaxy (MBE): From Research to Mass Production, Second Edition, provides a comprehensive overview of the latest MBE research and applications in epitaxial growth, along with a detailed discussion and ‘how to’ on processing molecular or atomic beams that occur on the surface of a heated crystalline substrate in a vacuum. The techniques addressed in the book can be deployed wherever precise thin-film devices with enhanced and unique properties for computing, optics or photonics are required. It includes new semiconductor materials, new device structures that are commercially available, and many that are at the advanced research stage. This second edition covers the advances made by MBE, both in research and in the mass production of electronic and optoelectronic devices. Enhancements include new chapters on MBE growth of 2D materials, Si-Ge materials, AIN and GaN materials, and hybrid ferromagnet and semiconductor structures. Condenses the fundamental science of MBE into a modern reference, speeding up literature review Discusses new materials, novel applications and new device structures, grounding current commercial applications with modern understanding in industry and research Includes coverage of MBE as mass production epitaxial technology and how it enhances processing efficiency and throughput for the semiconductor industry and nanostructured semiconductor materials research community
Download or read book GaN based Materials and Devices written by Michael Shur and published by World Scientific. This book was released on 2004 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: The unique materials properties of GaN-based semiconductors have stimulated a great deal of interest in research and development regarding nitride materials growth and optoelectronic and nitride-based electronic devices. High electron mobility and saturation velocity, high sheet carrier concentration at heterojunction interfaces, high breakdown field, and low thermal impedance of GaN-based films grown over SiC or bulk AlN substrates make nitride-based electronic devices very promising. The chemical inertness of nitrides is another key property.This volume, written by experts on different aspects of nitride technology, addresses the entire spectrum of issues related to nitride materials and devices, and it will be useful for technologists, scientists, engineers, and graduate students who are working on wide bandgap materials and devices. The book can also be used as a supplementary text for graduate courses on wide bandgap semiconductor technology.
Download or read book Growth of Alinn and Zinc Blende Gan by Molecular Beam Epitaxy written by Min Shi and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Growth of AlInN and Zinc Blende GaN by Molecular Beam Epitaxy" by Min, Shi, 施敏, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled "GROWTH OF AlInN AND ZINC BLENDE GaN BY MOLECULAR BEAM EPITAXY" Submitted by SHI MIN for the degree of Master of Philosophy at The University of Hong Kong in December 2007 III-Nitrides have attracted wide interest in both their growth mechanism and applications. In this thesis, two issues of these materials are addressed via a detailed study by Molecular Beam Epitaxy (MBE) and various analysis techniques. One is cubic phase GaN growth while the other is the synthesis of AlInN alloys with composition control and morphology examinations. GaN exists in two polytypes, wurtzite and zinc blende. The effect of growth condition on crystallography during homoepitaxial deposition by MBE is thor- oughly investigated. It is found that at low substrate temperatures but high galliumfluxes, metastablezinc-blendephaseofGaNfilmsareobtained, whereas at high temperatures and/or using high nitrogen fluxes, equilibrium wurtzite phaseGaNepilayersresult. Thedepositionrateisfoundtohavenegligibleinflu- ence on the phase selection of the crystal. By Scanning Tunnelling Microscopy (STM), two-dimensional nucleation islands of GaN are examined. From the island shape and orientation, nuclei of cubic and wurtzite phase GaN can be identified, basedonwhichtheratiosbetweencubicandwurtzitenucleationsare deducedatvariousconditions. Theresultsrevealthatislandsofcubicphaseare favoured at lower temperature while at higher temperature, those of wurtzite phase dominate. This phase preference indicates that wurtzite to zinc blende phasetransitionbyMBEatlowertemperatureisakineticprocessratherthanathermodynamic one. It also points out that cubic phase GaN growth originate from the nucleation rather than some post-nucleation mechanisms. For AlInN alloy growth, contrasting to theoretical predictions counting only thermodynamic factors, AlInN synthesized by MBE is found to be well al- loyed under proper conditions, again, due to the kinetics feature of this growth method. It is also found that the composition of the ternary alloy can be tuned by either changing the metal flux ratio considering different incorporation rates ofthemetals, orbyalteringthetemperatureofsubstratewithafixedmetalflux ratio. The incorporation rates of both Al and In are estimated by a compar- ison between calibrated metal flux and the measurements by High-Resolution Transmission Electron Microscopy. It is found that Al incorporation is close to unity while only about half of the In flux incorporates into the alloy film. Furthermore, In incorporation is found to be strongly influenced by substrate temperature such that high growth temperature will result in lower In content even if the source flux remains constant. Highly ordered nanowires are observed by STM during the early stage in AlInN deposition on GaN(0001) surface. These nanowires are formed by aggre- gation of adatoms along GaN steps. The morphology is investigated in respect of deposition temperature, coverage, metal flux ratio and metal-nitrogen ra- tio. The surface states and electronic structure of such nanostructures are also studied by tunnelling spectroscopy technique. DOI: 10.5353/th_b3955887 Subjects: Gallium nitride Molecular beam epitaxy Indium alloys Aluminum alloys
Download or read book Handbook of Self Assembled Semiconductor Nanostructures for Novel Devices in Photonics and Electronics written by Mohamed Henini and published by Elsevier. This book was released on 2011-07-28 with total page 862 pages. Available in PDF, EPUB and Kindle. Book excerpt: The self-assembled nanostructured materials described in this book offer a number of advantages over conventional material technologies in a wide range of sectors. World leaders in the field of self-organisation of nanostructures review the current status of research and development in the field, and give an account of the formation, properties, and self-organisation of semiconductor nanostructures. Chapters on structural, electronic and optical properties, and devices based on self-organised nanostructures are also included. Future research work on self-assembled nanostructures will connect diverse areas of material science, physics, chemistry, electronics and optoelectronics. This book will provide an excellent starting point for workers entering the field and a useful reference to the nanostructured materials research community. It will be useful to any scientist who is involved in nanotechnology and those wishing to gain a view of what is possible with modern fabrication technology. Mohamed Henini is a Professor of Applied Physics at the University of Nottingham. He has authored and co-authored over 750 papers in international journals and conference proceedings and is the founder of two international conferences. He is the Editor-in-Chief of Microelectronics Journal and has edited three previous Elsevier books. Contributors are world leaders in the field Brings together all the factors which are essential in self-organisation of quantum nanostructures Reviews the current status of research and development in self-organised nanostructured materials Provides a ready source of information on a wide range of topics Useful to any scientist who is involved in nanotechnology Excellent starting point for workers entering the field Serves as an excellent reference manual
Download or read book Molecular Beam Epitaxy Growth and Characterization of GaN AlN and AlGaN GaN Heterostructures written by Stefan Davidsson and published by . This book was released on 2005 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MBE Growth and Characterization of Gan Film written by Wenkai Zhu and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "MBE Growth and Characterization of GaN Film" by Wenkai, Zhu, 朱文凱, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. DOI: 10.5353/th_b3122217 Subjects: Gallium nitride Molecular beam epitaxy
Download or read book Handbook of Nitride Semiconductors and Devices Materials Properties Physics and Growth written by Hadis Morkoç and published by John Wiley & Sons. This book was released on 2009-07-30 with total page 1311 pages. Available in PDF, EPUB and Kindle. Book excerpt: The three volumes of this handbook treat the fundamentals, technology and nanotechnology of nitride semiconductors with an extraordinary clarity and depth. They present all the necessary basics of semiconductor and device physics and engineering together with an extensive reference section. Volume 1 deals with the properties and growth of GaN. The deposition methods considered are: hydride VPE, organometallic CVD, MBE, and liquid/high pressure growth. Additionally, extended defects and their electrical nature, point defects, and doping are reviewed.
Download or read book Handbook of GaN Semiconductor Materials and Devices written by Wengang (Wayne) Bi and published by CRC Press. This book was released on 2017-10-20 with total page 709 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses material growth, device fabrication, device application, and commercialization of energy-efficient white light-emitting diodes (LEDs), laser diodes, and power electronics devices. It begins with an overview on basics of semiconductor materials, physics, growth and characterization techniques, followed by detailed discussion of advantages, drawbacks, design issues, processing, applications, and key challenges for state of the art GaN-based devices. It includes state of the art material synthesis techniques with an overview on growth technologies for emerging bulk or free standing GaN and AlN substrates and their applications in electronics, detection, sensing, optoelectronics and photonics. Wengang (Wayne) Bi is Distinguished Chair Professor and Associate Dean in the College of Information and Electrical Engineering at Hebei University of Technology in Tianjin, China. Hao-chung (Henry) Kuo is Distinguished Professor and Associate Director of the Photonics Center at National Chiao-Tung University, Hsin-Tsu, Taiwan, China. Pei-Cheng Ku is an associate professor in the Department of Electrical Engineering & Computer Science at the University of Michigan, Ann Arbor, USA. Bo Shen is the Cheung Kong Professor at Peking University in China.
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2668 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigations of the GaN AlN and InN Semiconductors Structural Optical Electronic and Interfacial Properties written by and published by . This book was released on 1993 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Described in this thesis is an investigation of some fundamental physical properties of both zincblende and wurtzite Group III - Nitride wide bandgap semiconductor materials. All of the thin films studied were grown by plasma-enhanced molecular beam epitaxy on either GaAs and SiC substrates. This growth method proved to be suitable for nitride expitaxial growth although compromises between the plasma power and the crystal growth rate had to be sought. The zincblende polytypes of GaN and InN were studied with the intent of evaluating their potential as a wide bandgap semiconductor system for short wavelength optical devices. The metastability of these crystals has led us to the conclusion that the zincblende nitrides are not a promising candidate for these applications due to their tendency to nucleate wurtzite domains. Bulk samples of zincblende GaN and InN and wurtzite GaN, AlN and InN were studied by x-ray photoemission spectroscopy (XPS) in an effort to determine their valence band structure. We report the various energies of the valence band density of states maxima as well as the ionicity gaps of each material. Wurtzite GaN/AlN and InN/AlN heterostructures were also investigated by XPS in order to estimate the valence band discontinuities of these heterojunctions. We measured valence band discontinuities of deltaEv(GaN/AlN) = 0.4 +/- 0.4 eV and deltaEv(InN/AlN) = 1.1 +/- 0.4 eV. Our results indicate that both systems have heterojunction band lineups fundamentally suitable for common optical device applications.
Download or read book Characterization and Doping of Epitaxially Grown GaN and A1N on Si Using Molecular Beam Epitaxy written by Chi Hang Ko and published by . This book was released on 2007 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitride based semiconductors have a unique combination of properties that make them especially suitable for many of the new challenges and applications of the twenty-first century, The group III nitride semiconductors, aluminum nitride (AlN), gallium nitride (GaN), and indium nitride (InN) form a complete series of ternary alloys (InGaN, InAlN, and AlGaN) whose direct band gaps range from 1.9 to 6.2 eV. These compound semiconductors far exceed the physical properties of silicon, and GaN is the most dynamic of them. GaN is often referred to as the "final frontier of semiconductors", Its high thermal conductivity, high melting temperature, low dielectric constant and high breakdown voltage make it an attractive semiconductor for many electronic and optoelectronic devices such as light emitting diodes, laser diodes, radiation detectors, high power and high frequency devices capable of operating at high temperatures, and in hostile chemical environments and so on, GaN thin films, either intrinsic or doped with silicon or magnesium, were grown on silicon(lll) substrates with AIN buffer layers by Molecular Beam Epitaxy (MBE) under a broad range of growth parameters in this study. The samples were characterized using Filmetrics thin film analyzer, Atomic Force Microscopy (AFM), Photoluminescence Spectroscopy, hot probe, and four-point probe. Material growth began with deposition of a 0.3 monolayer (ML) of Al on the SiC 111) 7x7 surface leading to fully passivated Si(111) [square root]3x[square root]3-Al surface, on which AlN buffer layers and then the GaN layers were deposited. X-ray diffraction measurements indicated growth of single-crystalline hexagonal GaN(00l) while PL measurement demonstrated a peak position corresponding to bulk hexagonal GaN, Sample surface morphology, roughness, and resistivity showed a strong dependence on growth conditions and dopant types. The percent roughness/thickness on the GaN fIlms decreased linearly with increasing Si dopant temperature and increased exponentially to the first order with increasing Mg dopant temperature. P-type doping was achieved using Mg and the resistivity of both Si- and Mg-doped GaN samples showed an inverse linear relationship with the dopant temperatures.
Download or read book Growth Nitrogen Vacancy Reduction and Solid Solution Formation in Cubic GaN Thin Films and the Subsequent Fabrication of Superlattice Structures Using AlN and InN written by and published by . This book was released on 1992 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Undoped GaN films have been deposited by gas-source MBE having essentially intrinsic electrical character. Acceptor-type behavior has been achieved with Mg doping. The electrical properties of these latter films were resistivity = 0.5 omega (dot) cm, Hall mobility (holes = 10 cm2/V (dot) s and carrier concentration = 1 x 10(18) cm-3. Photo-assisted gas-source MBE growth of stoichiometric GaN has also been achieved using a 500 W Hg lamp. Illumination and Ga cell temperature altered the texture of the polycrystalline GaN in unusual ways, changing the growth habit from (0001) is parallel to (100) to (0001) is parallel to (111) and back again. Thin films of cubic-BN (c-BN) have also been deposited on various substrates via both gas-source MBE and electron beam MBE. The use of Si (100) substrates, the latter technique and the characterization tools of RHEED, XPS, LEED, SEM, FTIR and HRTEM resulted in the achievement of an initial amorphous BN layer followed by a layer of turbostratic BN and subsequently by a layer of cubic BN. Cubic BN films were also deposited on polycrystalline diamond films grown via CVD on Si(100). The effect of the bombarding species was examined. Finally, the plans for both a systematic investigation of the ion implantation and contact development and related characterization of AlN and GaN with n- and p-type dopants and the construction and employment of a UV luminescence facility is discussed.
Download or read book Hot wall Low Pressure Chemical Vapor Deposition Growth and Characterization of GaN and Epitaxial AlN on Si 111 written by Karen Heinselman and published by . This book was released on 2016 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: The physical and electronic properties of aluminum nitride (AlN) have made it attractive for a wide variety of applications, including bulk and surface acoustic wave (B/SAW) resonators and thin film dielectric coatings. Due to its wide band gap of 6.2 eV, AlN is a good insulator. The chemical durability of AlN makes it appealing for extreme environmental conditions. Its thermal expansion coefficient is similar to those of other semiconductor materials such as Si and SiC, making it appropriate for use in high temperature applications as well. In this work, we demonstrate the growth of AlN and GaN thin films using hotwall low pressure chemical vapor deposition (LPCVD) in order to obtain epitaxial AlN growth with a parallelizable, inexpensive method (relative to the current epitaxial growth method, molecular beam epitaxy). This dissertation demonstrates the growth of aluminum nitride thin films (between 70 nm and 1 [MICRO SIGN]m in thickness) on Si (111) substrates using hot-wall low pressure chemical vapor deposition (LPCVD) at 1000 ? C and 2 torr. Prior to growth, the substrates were pretreated in situ with dichlorosilane cleaning step, the parameters of which were varied to optimize the c-axis alignment of the grown thin film AlN. In addition, nucleation time for the aluminum precursor, trimethylaluminum (TMAl) was varied and optimized. X-ray diffraction (XRD) was performed on the samples for characterization. With the optimal nucleation time and dichlorosilane pretreatment, the 2[theta]-[omega] FWHM of the resulting AlN film was 1160 arcsec, and the FWHM of the [omega] rocking curve was 1.6? . These optimal parameters exhibited epitaxial AlN peaks aligned with the Si (111) substrate when characterized using a tilted phi scan XRD technique. Transmission electron microscopy (TEM) provides a second epitaxial alignment confirmation. Backside etching of the Si (111) substrate to create freestanding AlN thin film drums is demonstrated. This access to the back side of the AlN thin films allows the fabrication of future bulk acoustic wave (BAW) resonator devices and testing the piezoelectric response of these materials. For alternate applications, GaN was grown on AlN buffer layers on Si (111) substrates using hot-wall LPCVD. The resulting film was c-axis aligned, with an XRD FWHM of 1420 arcsec for the GaN (001) 2[theta]-[omega] peak, and the FWHM of the rocking curve was 3.8? . Capacitance-voltage data on the grown GaN on AlN indicate n-type films with residual electron concentrations of roughly 1017 cm[-]3 .
