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The InGaN Material System and Blue/Green Emitters

  • Ning Zhang
  • Zhiqiang LiuEmail author
Chapter
Part of the Solid State Lighting Technology and Application Series book series (SSLTA, volume 4)

Abstract

Due to the advantage of low-power consumption, long lifetime, and high efficiency, nitride-based light-emitting diodes (LEDs) have long been considered to be a promising technology for next-generation illumination. The efforts on this topic could be tracked back to the 1950s. The possibility of a new lighting technology using GaN was considered by Philips Research Laboratories in the 1950s, and the photoluminescence of GaN power was obtained by H.G. Grimmeiss and H. Koelmans. The first single-crystal film of GaN was prepared by Maruska and Tietjenusing, the HVPE technique in 1969. At the end of the 1980s, the breakthrough of Amano, Akasaki, and Nakamura on p doping opened the way to p-n junctions in GaN. Another crucial step in developing efficient blue LEDs was the growth of alloys (AlGaN, InGaN), which are necessary to produce heterojunctions. In 1994, Nakamura and co-workers achieved a quantum efficiency of 2.7% using a double heterojunction InGaN/AlGaN. It was the first step toward the commercial development of efficient nitride LEDs, and their tremendous application was open. Today’s efficient of LEDs is the result of a long series of breakthroughs in fundamental materials physics and high-quality crystal growth, in device physics with advanced heterostructure design, and in optical physics for light extraction. And the application will continue to expand to many novel fields. At the same time, the efficiency, which relates to fundamental physics, growth, and fabrication, still needs to be further improved. In this chapter, some pioneering and significant experiment results.

In this work, we will focus on two important wavelength range of nitride LEDs, namely, blue and green one. We describe a number of factors that affect the efficiency of LEDs and analyze the effects of polarization, carrier transport, carrier localization, current expansion, epitaxial structure design, Auger recombination, and light extraction. Some pioneering and significant experiment results will be presented. We hope it can provide some meaningful information for the development of high-efficiency GaN-based blue and green LEDs.

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© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Institute of Semiconductors, Chinese Academy of SciencesBeijingChina
  2. 2.State Key Laboratory of Solid State LightingBeijingChina
  3. 3.Beijing Engineering Research Center for the 3rd Generation Semiconductor Materials and ApplicationBeijingChina

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