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Mocvd Growth And Characterization Of Nonpolar And Semipolar Gan Based Green Laser Diodes
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Book Synopsis MOCVD Growth and Characterization of Nonpolar and Semipolar GaN-based Green Laser Diodes by : You-Da Lin
Download or read book MOCVD Growth and Characterization of Nonpolar and Semipolar GaN-based Green Laser Diodes written by You-Da Lin and published by . This book was released on 2010 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Direct emission green laser diodes (LDs) have been drawing significant attention as a compact and efficient light source for pico-projector and LD display applications. GaN-based LDs are promising candidates for blue and green LDs. Unlike LDs grown on c-plane GaN, LDs grown on nonpolar or semipolar GaN substrates have no or less polarization - induced electric fields in the quantum wells leading to the possibility of better device performance.
Book Synopsis The Blue Laser Diode by : Shuji Nakamura
Download or read book The Blue Laser Diode written by Shuji Nakamura and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1993, the author, Shuji Nakamura developed the first commercially available blue and green light-emitting diodes. Now he has made the most important breakthrough in solid state laser techniques to date - the first blue semiconductor laser based on GaN. Here, Dr. Nakamura discusses the physical concept and basic manufacturing technology of these new blue light-emitting and laser diodes. he shows how this represents a new era in commercial applications for semiconductors, including displays, road and railway signalling, lighting, scanners, optical data storage, and much more. Moreover, Nakamura provides fascinating background information on the extraordinary realisation of an extremely successful concept of research and development. Of interest to researchers as well as engineers.
Book Synopsis MOVPE growth and characterization of (In,Ga)N quantum structures for laser diodes emitting at 440 nm by : Veit Hoffmann
Download or read book MOVPE growth and characterization of (In,Ga)N quantum structures for laser diodes emitting at 440 nm written by Veit Hoffmann and published by Cuvillier Verlag. This book was released on 2012-03-13 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis describes growth and characterization of nitride-based quantum well structures for laser diodes emitting in the wavelength range between 400 nm and 450 nm. In order optimize the epitaxial growth process by metal organic vapor phase epitaxy and thus the performance of the laser diode structures, the material properties of the indium gallium nitride (InGaN) active region were correlated with device characteristics. By analyzing optically pumpable laser structures in a first step, growth conditions and growth schemes were revealed that prevent 3D growth and the formation of additional defects in the active region. In the next step, using growth parameter that provide a high material gain broad area current injection laser diodes emitting around 400 nm were realized on sapphire substrate. These devices feature threshold current densities in the range of 6 kA/cm² in pulsed operation. For laser diodes emitting at longer wavelengths, the heterostructure layout was optimized by comparing optical pumping results with device simulation. Using a layer sequence with increased modal gain, first broad area current injection laser diodes emitting around 440 nm were demonstrated. The structures were grown on low defect density bulk GaN substrates and exhibit threshold current densities of ~10 kA/cm² in pulsed operation. On the basis of these results further device and process development was started aiming for ridge waveguide laser structures operating continuous wave in the wavelength range between 400 and 450 nm.
Book Synopsis Nonpolar M-plane GaN-based Laser Diodes in the Blue Spectrum by : Kathryn Merced Kelchner
Download or read book Nonpolar M-plane GaN-based Laser Diodes in the Blue Spectrum written by Kathryn Merced Kelchner and published by . This book was released on 2012 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gallium nitride (GaN), together with its alloys with aluminum and indium, have revolutionized the solid-state optoelectronics market for their ability to emit a large portion of the visible electromagnetic spectrum from deep ultraviolet and into the infrared. GaN-based semiconductor laser diodes (LDs) with emission wavelengths in the violet, blue and green are already seeing widespread implementation in applications ranging from energy storage, lighting and displays. However, commercial GaN-based LDs use the basal c-plane orientation of the wurtzite crystal, which can suffer from large internal electric fields due to discontinuities in spontaneous and piezoelectric polarizations, limiting device performance. The nonpolar orientation of GaN benefits from the lack of polarization-induced electric field as well as enhanced gain. This dissertation discusses some of the benefits and limitations of m-plane oriented nonpolar GaN for LD applications in the true blue spectrum (450 nm). Topics include an overview of material growth by metal-organic chemical vapor deposition (MOCVD), waveguide design and processing techniques for improving device performance for multiple lateral mode and single lateral mode ridge waveguides.
Book Synopsis The Blue Laser Diode by : Shuji Nakamura
Download or read book The Blue Laser Diode written by Shuji Nakamura and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews of the first edition: "The technical chapters will be lapped up by semiconductor specialists keen to know more [...] the book includes fascinating material that answers the question: why did Nakamura succeed where many, much larger, research groups failed." New Scientist
Book Synopsis 500 Nm Semipolar GaN-based Laser Diodes by : Anurag Tyagi
Download or read book 500 Nm Semipolar GaN-based Laser Diodes written by Anurag Tyagi and published by . This book was released on 2011 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last few years the availability of nonpolar/semipolar bulk GaN substrates has spurred intense research efforts towards the realization of novel GaN-based optoelectronic devices. Growth of (Al, In, Ga)N heterostructures on non-basal planes of wurtzite GaN leads to reduced/absent polarization-related internal electric fields and consequently, offers the possibility of improved device performance.
Book Synopsis Beyond Conventional C-plane GaN-based Light Emitting Diodes by : Morteza Monavarian
Download or read book Beyond Conventional C-plane GaN-based Light Emitting Diodes written by Morteza Monavarian and published by . This book was released on 2016 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite enormous efforts and investments, the efficiency of InGaN-based green and yellow-green light emitters remains relatively low, and that limits progress in developing full color display, laser diodes, and bright light sources for general lighting. The low efficiency of light emitting devices in the green-to-yellow spectral range, also known as the "Green Gap", is considered a global concern in the LED industry. The polar c-plane orientation of GaN, which is the mainstay in the LED industry, suffers from polarization-induced separation of electrons and hole wavefunctions (also known as the "quantum confined Stark effect") and low indium incorporation efficiency that are the two main factors that contribute to the Green Gap phenomenon. One possible approach that holds promise for a new generation of green and yellow light emitting devices with higher efficiency is the deployment of nonpolar and semi-polar crystallographic orientations of GaN to eliminate or mitigate polarization fields. In theory, the use of other GaN planes for light emitters could also enhance the efficiency of indium incorporation compared to c-plane. In this thesis, I present a systematic exploration of the suitable GaN orientation for future lighting technologies. First, in order to lay the groundwork for further studies, it is important to discuss the analysis of processes limiting LED efficiency and some novel designs of active regions to overcome these limitations. Afterwards, the choice of nonpolar orientations as an alternative is discussed. For nonpolar orientation, the (1-100)-oriented (m-plane) structures on patterned Si (112) and freestanding m-GaN are studied. The semi-polar orientations having substantially reduced polarization field are found to be more promising for light-emitting diodes (LEDs) owing to high indium incorporation efficiency predicted by theoretical studies. Thus, the semi-polar orientations are given close attention as alternatives for future LED technology. One of the obstacles impeding the development of this technology is the lack of suitable substrates for high quality materials having semi-polar and nonpolar orientations. Even though the growth of free-standing GaN substrates (homoepitaxy) could produce material of reasonable quality, the native nonpolar and semi-polar substrates are very expensive and small in size. On the other hand, GaN growth of semi-polar and nonpolar orientations on inexpensive, large-size foreign substrates (heteroepitaxy), including silicon (Si) and sapphire (Al2O3), usually leads to high density of extended defects (dislocations and stacking faults). Therefore, it is imperative to explore approaches that allow the reduction of defect density in the semi-polar GaN layers grown on foreign substrates. In the presented work, I develop a cost-effective preparation technique of high performance light emitting structures (GaN-on-Si, and GaN-on-Sapphire technologies). Based on theoretical calculations predicting the maximum indium incorporation efficiency at [theta] ~ 62° ([theta] being the tilt angle of the orientation with respect to c-plane), I investigate (11-22) and (1-101) semi-polar orientations featured by [theta] = 58̊° and [theta] = 62°, respectively, as promising candidates for green emitters. The (11-22)-oriented GaN layers are grown on planar m-plane sapphire, while the semi-polar (1-101) GaN are grown on patterned Si (001). The in-situ epitaxial lateral overgrowth techniques using SiNx nanoporous interlayers are utilized to improve the crystal quality of the layers. The data indicates the improvement of photoluminescence intensity by a factor of 5, as well as the improvement carrier lifetime by up to 85% by employing the in-situ ELO technique. The electronic and optoelectronic properties of these nonpolar and semi-polar planes include excitonic recombination dynamics, optical anisotropy, exciton localization, indium incorporation efficiency, defect-related optical activities, and some challenges associated with these new technologies are discussed. A polarized emission from GaN quantum wells (with a degree of polarization close to 58%) with low non-radiative components is demonstrated for semi-polar (1-101) structure grown on patterned Si (001). We also demonstrated that indium incorporation efficiency is around 20% higher for the semi-polar (11-22) InGaN quantum wells compared to its c-plane counterpart. The spatially resolved cathodoluminescence spectroscopy demonstrates the uniform distribution of indium in the growth plane. The uniformity of indium is also supported by the relatively low exciton localization energy of Eloc = 7meV at 15 K for these semi-polar (11-22) InGaN quantum wells compared to several other literature reports on c-plane. The excitons are observed to undergo radiative recombination in the quantum wells in basal-plane stacking faults at room temperature. The wurtzite/zincblende electronic band-alignment of BSFs is proven to be of type II using the time-resolved differential transmission (TRDT) method. The knowledge of band alignment and degree of carrier localization in BSFs are extremely important for evaluating their effects on device properties. Future research for better understanding and potential developments of the semi-polar LEDs is pointed out at the end.
Book Synopsis Ohmic Backside Contact for Nonpolar/semipolar GaN-based Cleaved-facet Green Laser Diodes by : Chia-Lin Hsiung
Download or read book Ohmic Backside Contact for Nonpolar/semipolar GaN-based Cleaved-facet Green Laser Diodes written by Chia-Lin Hsiung and published by . This book was released on 2010 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Characterization of N-polar InGaN/GaN Light Emitting Diodes Grown by MOCVD by : Motoko Furukawa
Download or read book Characterization of N-polar InGaN/GaN Light Emitting Diodes Grown by MOCVD written by Motoko Furukawa and published by . This book was released on 2007 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Analysis of Gain and Absorption Spectra of GaN-based Laser Diodes by : Thiago Pantaleao Melo
Download or read book Analysis of Gain and Absorption Spectra of GaN-based Laser Diodes written by Thiago Pantaleao Melo and published by . This book was released on 2012 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elimination or mitigation of polarization-related fields within the QWs grown along these novel orientations is observed and one expects increased radiative recombination rate and stabilization of the wavelength emission with respect to the injection current. In order to have more insights on the advantages of using the novel crystal orientations of the III-Nitride material system, we compare the gain of LD structures fabricated from c-plane, nonpolar and semipolar GaN substrates.
Book Synopsis Growth and Characterization of Non-polar GaN Materials and Investigation of Efficiency Droop in InGaN Light Emitting Diodes by : Xianfeng Ni
Download or read book Growth and Characterization of Non-polar GaN Materials and Investigation of Efficiency Droop in InGaN Light Emitting Diodes written by Xianfeng Ni and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: General lighting with InGaN light emitting diodes (LEDs) as light sources is of particular interest in terms of energy savings and related environmental benefits due to high lighting efficiency, long lifetime, and Hg-free nature. Incandescent and fluorescent light sources are used for general lighting almost everywhere. But their lighting efficiency is very limited: only 20-30 lm/W for incandescent lighting bulb, approximately 100 lm/W for fluorescent lighting. State-of-the-art InGaN LEDs with a luminous efficacy of over 200 lm/W at room temperature have been reported. However, the goal of replacing the incandescent and fluorescent lights with InGaN LEDs is still elusive since their lighting efficiency decreases substantially when the injection current increases beyond certain values (typically 10-50 Acm-2). In order to improve the electroluminescence (EL) performance at high currents for InGaN LEDs, two approaches have been undertaken in this thesis. First, we explored the preparation and characterization of non-polar and semi-polar GaN substrates (including a-plane, m-plane and semi-polar planes). These substrates serve as promising alternatives to the commonly used c-plane, with the benefit of a reduced polarization-induced electric field and therefore higher quantum efficiency. It is demonstrated that LEDs on m-plane GaN substrates have inherently higher EL quantum efficiency and better efficiency retention ability at high injection currents than their c-plane counterparts. Secondly, from a device structure level, we explored the possible origins of the EL efficiency degradation at high currents in InGaN LEDs and investigated the effect of hot electrons on EL of LEDs by varying the barrier height of electron blocking layer. A first-order theoretical model is proposed to explain the effect of electron overflow caused by hot electron transport across the LED active region on LED EL performance. The calculation results are in agreement with experimental observations. Furthermore, a novel structure called a "staircase electron injector" (SEI) is demonstrated to effectively thermalize hot electrons, thereby reducing the reduction of EL efficiency due to electron overflow. The SEI features several InyGa1-yN layers, with their In fraction (y) increasing in a stepwise manner, starting with a low value at the first step near the junction with n-GaN.
Book Synopsis Characterization and Comparison of 830 Nm Laser Diodes Fabricated in MOCVD and MBE Grown Heterostructures by : Balaji P. Ramamoorthy
Download or read book Characterization and Comparison of 830 Nm Laser Diodes Fabricated in MOCVD and MBE Grown Heterostructures written by Balaji P. Ramamoorthy and published by . This book was released on 1997 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Growth and Characterization of Polar and Semipolar Light Emitting Diodes by : Michael Iza
Download or read book Growth and Characterization of Polar and Semipolar Light Emitting Diodes written by Michael Iza and published by . This book was released on 2006 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Metalorganic Vapor Phase Epitaxy (MOVPE) by : Stuart Irvine
Download or read book Metalorganic Vapor Phase Epitaxy (MOVPE) written by Stuart Irvine and published by John Wiley & Sons. This book was released on 2019-10-07 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: Systematically discusses the growth method, material properties, and applications for key semiconductor materials MOVPE is a chemical vapor deposition technique that produces single or polycrystalline thin films. As one of the key epitaxial growth technologies, it produces layers that form the basis of many optoelectronic components including mobile phone components (GaAs), semiconductor lasers and LEDs (III-Vs, nitrides), optical communications (oxides), infrared detectors, photovoltaics (II-IV materials), etc. Featuring contributions by an international group of academics and industrialists, this book looks at the fundamentals of MOVPE and the key areas of equipment/safety, precursor chemicals, and growth monitoring. It covers the most important materials from III-V and II-VI compounds to quantum dots and nanowires, including sulfides and selenides and oxides/ceramics. Sections in every chapter of Metalorganic Vapor Phase Epitaxy (MOVPE): Growth, Materials Properties and Applications cover the growth of the particular materials system, the properties of the resultant material, and its applications. The book offers information on arsenides, phosphides, and antimonides; nitrides; lattice-mismatched growth; CdTe, MCT (mercury cadmium telluride); ZnO and related materials; equipment and safety; and more. It also offers a chapter that looks at the future of the technique. Covers, in order, the growth method, material properties, and applications for each material Includes chapters on the fundamentals of MOVPE and the key areas of equipment/safety, precursor chemicals, and growth monitoring Looks at important materials such as III-V and II-VI compounds, quantum dots, and nanowires Provides topical and wide-ranging coverage from well-known authors in the field Part of the Materials for Electronic and Optoelectronic Applications series Metalorganic Vapor Phase Epitaxy (MOVPE): Growth, Materials Properties and Applications is an excellent book for graduate students, researchers in academia and industry, as well as specialist courses at undergraduate/postgraduate level in the area of epitaxial growth (MOVPE/ MOCVD/ MBE).
Book Synopsis Technology of Gallium Nitride Crystal Growth by : Dirk Ehrentraut
Download or read book Technology of Gallium Nitride Crystal Growth written by Dirk Ehrentraut and published by Springer Science & Business Media. This book was released on 2010-06-14 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses the important technological aspects of the growth of GaN single crystals by HVPE, MOCVD, ammonothermal and flux methods for the purpose of free-standing GaN wafer production.
Book Synopsis Optoelectronic Devices by : M Razeghi
Download or read book Optoelectronic Devices written by M Razeghi and published by Elsevier. This book was released on 2004 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tremendous progress has been made in the last few years in the growth, doping and processing technologies of the wide bandgap semiconductors. As a result, this class of materials now holds significant promis for semiconductor electronics in a broad range of applications. The principal driver for the current revival of interest in III-V Nitrides is their potential use in high power, high temperature, high frequency and optical devices resistant to radiation damage. This book provides a wide number of optoelectronic applications of III-V nitrides and covers the entire process from growth to devices and applications making it essential reading for those working in the semiconductors or microelectronics. Broad review of optoelectronic applications of III-V nitrides
Download or read book JJAP Letters written by and published by . This book was released on 2006 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
