Enhanced light collection of GaN light emitting devices by redirecting the lateral emission using nanorod reflectors.
We demonstrate a method of utilizing self-assembled nanorod array reflectors to collect the laterally propagating guided modes from a light emitting diode (LED). We measure an enhancement factor of 12.2% and 18.4%, respectively, from the sidewall emission of GaN-based LEDs encompassed with 10 and 20 microm thick nanorod array reflectors. Such enhancement is found to be omnidirectional due to a broken symmetry from a randomized distribution of the nanorod array placed along the periphery of the LED's mesa. These observations indicate that the use of nanorod reflectors can efficiently redirect the propagation of the laterally guided modes to the surface normal direction.
Graduate Institute of Photonics and Optoelectronics, National Taiwan University, 1, Roosevelt Road, Section 4, Taipei, 106, Taiwan.
Yun-Wei
YW
Cheng
Kun-Mao
KM
Pan
Cheng-Yin
CY
Wang
Hung-Hsien
HH
Chen
Min-Yung
MY
Ke
Cheng-Pin
CP
Chen
Min-Yann
MY
Hsieh
Han-Ming
HM
Wu
Lung-Han
LH
Peng
JianJang
J
Huang