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
C.C. Shan
1
OUTLINE
Introduction LED Fabrication LED Performance Conclusions References
2
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.
3
LED FABRICATION
Sapphire (0001)
buffer 25nm
N-GaN 5um
MQWEBL
P-GaN
550*550um2
P
N
40nmLEDA:0%LEDB:22%LEDC:32%150nm
4
LED PERFORMANCE
FIG. 1. Color online V-I curves of the LEDs A, B, and C.5
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.
6