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EFFECT OF ELECTRON BLOCKING
LAYER ON EFFICIENCY DROOP IN
INGAN/GAN MULTIPLE QUANTUM
WELL LIGHT-EMITTING DIODES
SANG-HEON HAN, DONG-YUL LEE, SANG-JUN LEE, CHU-YOUNG CHO, MIN-KI KWON,
S. P. LEE,1 D. Y. NOH, DONG-JOON KIM, YONG CHUN KIM, AND SEONG-JU PARK, APPLIED PHYSICS
LETTERS 94, 231123 2009
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C.C. Shan
OUTLINE
 Introduction
 LED
Fabrication
 LED Performance
 Conclusions
 References
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INTRODUCTION
 Electron
overflow to the p-type region and
results in an efficiency droop.
 EBL
has effectively confining electrons in
the MQW region of most MQW LEDs.
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LED FABRICATION
550*550um2
P
P-GaN
40nm
150nm
EBL
MQW
LEDA:0%
LEDB:22%
LEDC:32%
N
N-GaN
5um
buffer
25nm
Sapphire (0001)
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LED PERFORMANCE
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FIG. 1. Color online V-I curves of the LEDs A, B, and C.
LED PERFORMANCE
FIG. 2. Color online Light output power vs current density of LEDs A, B, and C, a
at low current density and b at high current density.
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