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Title: High extraction efficiency ultraviolet light-emitting diode

Abstract

Ultraviolet light-emitting diodes with tailored AlGaN quantum wells can achieve high extraction efficiency. For efficient bottom light extraction, parallel polarized light is preferred, because it propagates predominately perpendicular to the QW plane and into the typical and more efficient light escape cones. This is favored over perpendicular polarized light that propagates along the QW plane which requires multiple, lossy bounces before extraction. The thickness and carrier density of AlGaN QW layers have a strong influence on the valence subband structure, and the resulting optical polarization and light extraction of ultraviolet light-emitting diodes. At Al>0.3, thinner QW layers (<2.5 nm are preferred) result in light preferentially polarized parallel to the QW plane. Also, active regions consisting of six or more QWs, to reduce carrier density, and with thin barriers, to efficiently inject carriers in all the QWs, are preferred.

Inventors:
; ;
Issue Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1226807
Patent Number(s):
9196788
Application Number:
14/480,072
Assignee:
Sandia Corporation (Albuquerque, NM)
Patent Classifications (CPCs):
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01L - SEMICONDUCTOR DEVICES
DOE Contract Number:  
AC04-94AL85000
Resource Type:
Patent
Resource Relation:
Patent File Date: 2014 Sep 08
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY

Citation Formats

Wierer, Jonathan, Montano, Ines, and Allerman, Andrew A. High extraction efficiency ultraviolet light-emitting diode. United States: N. p., 2015. Web.
Wierer, Jonathan, Montano, Ines, & Allerman, Andrew A. High extraction efficiency ultraviolet light-emitting diode. United States.
Wierer, Jonathan, Montano, Ines, and Allerman, Andrew A. Tue . "High extraction efficiency ultraviolet light-emitting diode". United States. https://www.osti.gov/servlets/purl/1226807.
@article{osti_1226807,
title = {High extraction efficiency ultraviolet light-emitting diode},
author = {Wierer, Jonathan and Montano, Ines and Allerman, Andrew A.},
abstractNote = {Ultraviolet light-emitting diodes with tailored AlGaN quantum wells can achieve high extraction efficiency. For efficient bottom light extraction, parallel polarized light is preferred, because it propagates predominately perpendicular to the QW plane and into the typical and more efficient light escape cones. This is favored over perpendicular polarized light that propagates along the QW plane which requires multiple, lossy bounces before extraction. The thickness and carrier density of AlGaN QW layers have a strong influence on the valence subband structure, and the resulting optical polarization and light extraction of ultraviolet light-emitting diodes. At Al>0.3, thinner QW layers (<2.5 nm are preferred) result in light preferentially polarized parallel to the QW plane. Also, active regions consisting of six or more QWs, to reduce carrier density, and with thin barriers, to efficiently inject carriers in all the QWs, are preferred.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2015},
month = {11}
}

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Works referenced in this record:

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