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Reliability of Ultraviolet Light-Emitting Diodes

  • Carlo De SantiEmail author
  • Desiree Monti
  • Pradip Dalapati
  • Matteo Meneghini
  • Gaudenzio Meneghesso
  • Enrico Zanoni
Chapter
Part of the Solid State Lighting Technology and Application Series book series (SSLTA, volume 4)

Abstract

This chapter presents an extensive review of the literature on the degradation processes of GaN-based UV-A, UV-B, and UV-C LEDs. For the state-of-the-art devices, the main open issue is the increase in Shockley–Read–Hall non-radiative recombination inside the quantum well, originating from local generation of defects or from diffusion processes of dopant atoms or foreign impurities. Temperature acts as a significant acceleration factor, especially in lower wavelength devices, affected by a higher turn-on voltage. Changes in the chemical structure of the package and of the encapsulant, induced by the high energy of the photons, may lead to a lower reflectivity and transmittance, thus limiting the overall reliability of the devices.

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • Carlo De Santi
    • 1
    Email author
  • Desiree Monti
    • 1
  • Pradip Dalapati
    • 1
  • Matteo Meneghini
    • 1
  • Gaudenzio Meneghesso
    • 1
  • Enrico Zanoni
    • 1
  1. 1.Department of Information EngineeringUniversity of PadovaPadovaItaly

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