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Title: Tailoring of polarization in electron blocking layer for electron confinement and hole injection in ultraviolet light-emitting diodes

The influence of the AlGaN electron blocking layer (EBL) with graded aluminum composition on electron confinement and hole injection in AlGaN-based ultraviolet light-emitting diodes (LEDs) are investigated. The light output power of LED with graded AlGaN EBL was markedly improved, comparing to LED with conventional EBL. In experimental results, a high increment of 86.7% can be obtained in light output power. Simulation analysis shows that via proper modification of the barrier profile from the last barrier of the active region to EBL, not only the elimination of electron overflow to p-type layer can be achieved but also the hole injection into the active region can be enhanced, compared to a conventional LED structure. The dominant factor to the performance improvement is shown to be the modulation of polarization field by the graded Al composition in EBL.
Authors:
;  [1] ; ;  [2] ;  [1] ;  [3] ;  [1] ;  [4] ;  [5]
  1. Department of Electrical Engineering, Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan (China)
  2. Electronics and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan (China)
  3. (United States)
  4. (China)
  5. Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, California 90095 (United States)
Publication Date:
OSTI Identifier:
22271191
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; ALUMINIUM COMPOUNDS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DEPLETION LAYER; ELECTRONS; GALLIUM NITRIDES; HOLES; LIGHT EMITTING DIODES; MODULATION; POLARIZATION; ULTRAVIOLET RADIATION