Light-Emitting Diodes

Light emitting diodes (LEDs) are devices that are used in a myriad of applications, such as indicator lights in instruments, signage, illuminations, and communication. This graduate textbook covers all aspects of the technology and physics of infrared, visible-spectrum, and white light-emitting diodes (LEDs) made from III-V semiconductors. It reviews elementary properties of LEDs such as the electrical and optical characteristics. Exercises and illustrative examples reinforce the topics discussed. This book covers all aspects of the technology and physics of infrared, visible-spectrum, and white light-emitting diodes (LEDs) made from III-V semiconductors. The book reviews elementary properties of LEDs such as the electrical and optical characteristics. The author also reviews advanced device physics including high-efficiency device designs, light extraction, radiative and non-radiative recombination dynamics, spontaneous recombination in resonant-cavity structures, and packaging. The reader is introduced to areas related to visible-spectrum and white LEDs such as human vision, photometry, colorimetry, and color rendering. Application of infrared and visible-spectrum LEDs in silica fiber, plastic fiber, and free-space communication is discussed. Extensive semiconductor material data, device design data, and analytic formulas governing the operation of LEDs are provided. Exercises and illustrative examples are used to reinforce the topics discussed. An introductory chapter reviews the historical developments and milestones of LED research and development. This textbook will be of interest to scientists and engineers working on LEDs, notably in lighting, illumination and signage, and also to graduate students in electrical engineering, applied physics, and materials science. Revised and fully up-dated, the second edition of this graduate textbook offers a comprehensive explanation of the technology and physics of LEDs such as infrared, visible-spectrum, ultraviolet, and white LEDs made from III-V semiconductors. Elementary properties such as electrical and optical characteristics are reviewed, followed by the analysis of advanced device structures. With nine additional chapters, the treatment of LEDs has been vastly expanded, including new material on device packaging, reflectors, UV LEDs, III-V nitride materials, solid-state sources for illumination applications, and junction temperature. Radiative and non-radiative recombination dynamics, methods for improving light extraction, high-efficiency and high-power device designs, white-light emitters with wavelength-converting phosphor materials, optical reflectors, and spontaneous recombination in resonant-cavity structures are discussed in detail. With exercises, solutions, and illustrative examples, this textbook will be of interest to scientists and engineers working on LEDs and graduate students in electrical engineering, applied physics, and materials science. This book covers all aspects of the technology and physics of infrared, visible-spectrum, and white-light-emitting diodes (LEDs) made from III–V semiconductors. It reviews elementary properties of LEDs such as the electrical and optical characteristics, as well as advanced device physics including high-efficiency device designs, light extraction, radiative and non-radiative recombination dynamics, spontaneous recombination in resonant-cavity structures, and packaging. It introduces related areas such as human vision, photometry, colorimetry, and color rendering. Application of infrared and visible-spectrum LEDs in silica fiber, plastic fiber, and free-space communication is discussed. Extensive semiconductor material data, device design data, and analytic formulas governing LED operation are provided. Exercises and illustrative examples are included and an introductory chapter reviews the historical developments and milestones of LED research and development. This textbook will be of interest to scientists and engineers working on LEDs, and to graduate students in electrical engineering, applied physics and materials science. Starting early in the twentieth century, light emission from a solid-state material, caused by an electrical power source, has been reported: a phenomenon termed electroluminescence. serendipity". The quantum efficiency of the amphoterically doped GaAs LEDs was five times greater than that of GaAs p-n junctions fabricated by Zn diffusion.