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Nonpolar M Plane Gan Based Laser Diodes In The Blue Spectrum
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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 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 AlGaN-cladding-free Nonpolar M-plane GaN-based Laser Diodes by : Mathew Corey Schmidt
Download or read book AlGaN-cladding-free Nonpolar M-plane GaN-based Laser Diodes written by Mathew Corey Schmidt and published by . This book was released on 2008 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: The recent demonstration of nonpolar GaN laser diode operation along with rapid device improvements signal a paradigm shift in GaN-based optoelectronic technology. Up until now, GaN optoelectronics have been trapped on the c-plane facet, where built-in polarization fields place limitations on device design and performance. The advent of bulk GaN substrates has allowed for the full exploration of not only the nonpolar m-plane facet, but all crystal orientations of GaN.
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 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 Advances in Semiconductor Lasers by :
Download or read book Advances in Semiconductor Lasers written by and published by Academic Press. This book was released on 2012-06-12 with total page 541 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductors and Semimetals has distinguished itself through the careful selection of well-known authors, editors, and contributors. Originally widely known as the "Willardson and Beer" Series, it has succeeded in publishing numerous landmark volumes and chapters. The series publishes timely, highly relevant volumes intended for long-term impact and reflecting the truly interdisciplinary nature of the field. The volumes in Semiconductors and Semimetals have been and will continue to be of great interest to physicists, chemists, materials scientists, and device engineers in academia, scientific laboratories and modern industry. The series publishes timely, highly relevant volumes intended for long-term impact and reflecting the truly interdisciplinary nature of the field
Book Synopsis Encyclopedia of Modern Optics by : Bob D. Guenther
Download or read book Encyclopedia of Modern Optics written by Bob D. Guenther and published by Academic Press. This book was released on 2018-02-14 with total page 2253 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Encyclopedia of Modern Optics, Second Edition, Five Volume Set provides a wide-ranging overview of the field, comprising authoritative reference articles for undergraduate and postgraduate students and those researching outside their area of expertise. Topics covered include classical and quantum optics, lasers, optical fibers and optical fiber systems, optical materials and light-emitting diodes (LEDs). Articles cover all subfields of optical physics and engineering, such as electro-optical design of modulators and detectors. This update contains contributions from international experts who discuss topics such as nano-photonics and plasmonics, optical interconnects, photonic crystals and 2D materials, such as graphene or holy fibers. Other topics of note include solar energy, high efficiency LED’s and their use in illumination, orbital angular momentum, quantum optics and information, metamaterials and transformation optics, high power fiber and UV fiber lasers, random lasers and bio-imaging. Addresses recent developments in the field and integrates concepts from fundamental physics with applications for manufacturing and engineering/design Provides a broad and interdisciplinary coverage of specialist areas Ensures that the material is appropriate for new researchers and those working in a new sub-field, as well as those in industry Thematically arranged and alphabetically indexed, with cross-references added to facilitate ease-of-use
Book Synopsis Design and fabrication of GaN-based laser diodes for single-mode and narrow-linewidth applications by : Luca Redaelli
Download or read book Design and fabrication of GaN-based laser diodes for single-mode and narrow-linewidth applications written by Luca Redaelli and published by Cuvillier Verlag. This book was released on 2013-12-11 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work, several aspects concerning (In,Al,Ga)N laser diodes with high spectral purity, designed for applications in spectroscopy, were studied. A complete fabrication process for ridgewaveguide laser diodes on GaN substrate was developed. The lateral size of the ridge waveguides was as narrow as 1.5 μm: this is necessary in order to achieve lateral single-mode lasing in (In,Al,Ga)N laser diodes. A peculiar property of (In,Al,Ga)N laser diodes is that, when the ridge is narrow, the threshold current strongly depends on the ridge etch depth. This phenomenon was investigated by fabricating laser diodes with different etch depths. For ridge widths below 2 μm, the threshold current of shallow-ridge devices was found to be more than two times larger than that of comparable deep-ridge devices. Moreover, in the lateral far-field patterns of shallow-ridge laser diodes, side-lobes were observed, which would support the hypothesis of strong index-antiguiding. The antiguiding factor at threshold was experimentally determined to be about 10, which is among the largest values ever published for (In,Al,Ga)N laser diodes. The devices were further studied by simulation, and the results confirmed that the carrier-induced index change in the quantum wells can compensate the lateral index step if the ridge is shallow. This, in turn, reduces the lateral optical confi nement, which increases the threshold current and generates side lobes in the far-fi eld patterns. Based on this research, blue and violet laser diodes suitable for packaging in TO cans and continuous-wave (CW) operation exceeding 50 mW were fabricated. An external cavity diode laser (ECDL) was also realized, which could be tuned over the spectral range 435 nm - 444 nm and provided a peak emission power of more than 27 mW CW at 439 nm. As an alternative approach to obtain a narrow spectral linewidth, the feasibility of monolithically integrated Bragg-gratings was studied.
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 Blue Laser and Light Emitting Diodes by : Akihiko Yoshikawa
Download or read book Blue Laser and Light Emitting Diodes written by Akihiko Yoshikawa and published by IOS Press. This book was released on 1996 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: Realization of the semiconductor laser diodes (LDs) operating in the blue wavelength region had been a 'dream' for a long time for the scientists working on widegap materials until just a few years ago. Quite remarkable progress has been made in the last few years the dream has come true. The first ZnSe-based blue/green LD was fabricated about four years ago and its officially reported life-time in CW operation exceeds 100 hours now; it is quickly approaching a practical use level. Further, GaN-based blue LDs have also been realized. In this way, the progress in these research fields is quite rapid. The work includes articles on bulk growth, epitaxy, doping and characterization, blue LDs and LEDs, and future prospects in both ZnSe-based and GaN-based areas.
Book Synopsis Novel Compound Semiconductor Nanowires by : Fumitaro Ishikawa
Download or read book Novel Compound Semiconductor Nanowires written by Fumitaro Ishikawa and published by CRC Press. This book was released on 2017-10-17 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: One dimensional electronic materials are expected to be key components owing to their potential applications in nanoscale electronics, optics, energy storage, and biology. Besides, compound semiconductors have been greatly developed as epitaxial growth crystal materials. Molecular beam and metalorganic vapor phase epitaxy approaches are representative techniques achieving 0D–2D quantum well, wire, and dot semiconductor III-V heterostructures with precise structural accuracy with atomic resolution. Based on the background of those epitaxial techniques, high-quality, single-crystalline III-V heterostructures have been achieved. III-V Nanowires have been proposed for the next generation of nanoscale optical and electrical devices such as nanowire light emitting diodes, lasers, photovoltaics, and transistors. Key issues for the realization of those devices involve the superior mobility and optical properties of III-V materials (i.e., nitride-, phosphide-, and arsenide-related heterostructure systems). Further, the developed epitaxial growth technique enables electronic carrier control through the formation of quantum structures and precise doping, which can be introduced into the nanowire system. The growth can extend the functions of the material systems through the introduction of elements with large miscibility gap, or, alternatively, by the formation of hybrid heterostructures between semiconductors and another material systems. This book reviews recent progresses of such novel III-V semiconductor nanowires, covering a wide range of aspects from the epitaxial growth to the device applications. Prospects of such advanced 1D structures for nanoscience and nanotechnology are also discussed.
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 Long Wavelength GaN Blue Laser (400-490nm) Development by :
Download or read book Long Wavelength GaN Blue Laser (400-490nm) Development written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Room temperature (RT) pulsed operation of blue nitride based multi-quantum well (MQW) laser diodes grown on c-plane sapphire substrates was achieved. Atmospheric pressure MOCVD was used to grow the active region of the device which consisted of a 10 pair In{sub 0.21}Ga{sub 0.79}N (2.5nm)/In{sub 0.07}Ga{sub 0.93}N (5nm) InGaN MQW. The threshold current density was reduced by a factor of 2 from 10 kA/cm2 for laser diodes grown on sapphire substrates to 4.8 kA/cm2 for laser diodes grown on lateral epitaxial overgrowth (LEO) GaN on sapphire. Lasing wavelengths as long as 425nm were obtained. LEDs with emission wavelengths as long as 500nm were obtained by increasing the Indium content. These results show that a reduction in nonradiative recombination from a reduced dislocation density leads to a higher internal quantum efficiency. Further research on GaN based laser diodes is needed to extend the wavelength to 490nm which is required for numerous bio-detection applications. The GaN blue lasers will be used to stimulate fluorescence in special dye molecules when the dyes are attached to specific molecules or microorganisms. Fluorescein is one commonly used dye molecule for chemical and biological warfare agent detection, and its optimal excitation wavelength is 490 nm. InGaN alloys can be used to reach this wavelength.
Book Synopsis Japanese Journal of Applied Physics by :
Download or read book Japanese Journal of Applied Physics written by and published by . This book was released on 2007 with total page 1384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Modern Aspects of Bulk Crystal and Thin Film Preparation by : Nikolai Kolesnikov
Download or read book Modern Aspects of Bulk Crystal and Thin Film Preparation written by Nikolai Kolesnikov and published by BoD – Books on Demand. This book was released on 2012-01-13 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: In modern research and development, materials manufacturing crystal growth is known as a way to solve a wide range of technological tasks in the fabrication of materials with preset properties. This book allows a reader to gain insight into selected aspects of the field, including growth of bulk inorganic crystals, preparation of thin films, low-dimensional structures, crystallization of proteins, and other organic compounds.
Book Synopsis Polarization Effects in Semiconductors by : Colin Wood
Download or read book Polarization Effects in Semiconductors written by Colin Wood and published by Springer Science & Business Media. This book was released on 2007-10-16 with total page 523 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the latest understanding of the solid physics, electronic implications and practical applications of the unique spontaneous or pyro-electric polarization charge of hexagonal semiconductors, and the piezo-electric effects in thin film hetero-structures which are used in wide forbidden band gap sensor, electronic and opto-electronic semiconductor devices.
Book Synopsis GaN-Based Laser Diodes by : Wolfgang G. Scheibenzuber
Download or read book GaN-Based Laser Diodes written by Wolfgang G. Scheibenzuber and published by Springer. This book was released on 2012-01-29 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: The emergence of highly efficient short-wavelength laser diodes based on the III-V compound semiconductor GaN has not only enabled high-density optical data storage, but is also expected to revolutionize display applications. Moreover, a variety of scientific applications in biophotonics, materials research and quantum optics can benefit from these versatile and cost-efficient laser light sources in the near-UV to green spectral range. This thesis describes the device physics of GaN-based laser diodes, together with recent efforts to achieve longer emission wavelengths and short-pulse emission. Experimental and theoretical approaches are employed to address the individual device properties and optimize the laser diodes toward the requirements of specific applications.
