Efficiency droop in InGaN/GaN blue light-emitting diodes: Physical mechanisms and remedies
10.1063/1.4816434
Crossref journal-article
AIP Publishing
Journal of Applied Physics (317)
Abstract

Physical mechanisms causing the efficiency droop in InGaN/GaN blue light-emitting diodes and remedies proposed for droop mitigation are classified and reviewed. Droop mechanisms taken into consideration are Auger recombination, reduced active volume effects, carrier delocalization, and carrier leakage. The latter can in turn be promoted by polarization charges, inefficient hole injection, asymmetry between electron and hole densities and transport properties, lateral current crowding, quantum-well overfly by ballistic electrons, defect-related tunneling, and saturation of radiative recombination. Reviewed droop remedies include increasing the thickness or number of the quantum wells, improving the lateral current uniformity, engineering the quantum barriers (including multi-layer and graded quantum barriers), using insertion or injection layers, engineering the electron-blocking layer (EBL) (including InAlN, graded, polarization-doped, and superlattice EBL), exploiting reversed polarization (by either inverted epitaxy or N-polar growth), and growing along semi- or non-polar orientations. Numerical device simulations of a reference device are used through the paper as a proof of concept for selected mechanisms and remedies.

Bibliography

Verzellesi, G., Saguatti, D., Meneghini, M., Bertazzi, F., Goano, M., Meneghesso, G., & Zanoni, E. (2013). Efficiency droop in InGaN/GaN blue light-emitting diodes: Physical mechanisms and remedies. Journal of Applied Physics, 114(7).

Authors 7
  1. Giovanni Verzellesi (first)
  2. Davide Saguatti (additional)
  3. Matteo Meneghini (additional)
  4. Francesco Bertazzi (additional)
  5. Michele Goano (additional)
  6. Gaudenzio Meneghesso (additional)
  7. Enrico Zanoni (additional)
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Dates
Type When
Created 12 years ago (Aug. 16, 2013, 8:12 a.m.)
Deposited 2 years, 1 month ago (July 6, 2023, 1:09 a.m.)
Indexed 1 week, 5 days ago (Aug. 23, 2025, 9:25 p.m.)
Issued 12 years ago (Aug. 15, 2013)
Published 12 years ago (Aug. 15, 2013)
Published Online 12 years ago (Aug. 15, 2013)
Published Print 12 years ago (Aug. 21, 2013)
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@article{Verzellesi_2013, title={Efficiency droop in InGaN/GaN blue light-emitting diodes: Physical mechanisms and remedies}, volume={114}, ISSN={1089-7550}, url={http://dx.doi.org/10.1063/1.4816434}, DOI={10.1063/1.4816434}, number={7}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={Verzellesi, Giovanni and Saguatti, Davide and Meneghini, Matteo and Bertazzi, Francesco and Goano, Michele and Meneghesso, Gaudenzio and Zanoni, Enrico}, year={2013}, month=aug }