AVS 61st International Symposium & Exhibition
    Electronic Materials and Processing Friday Sessions
       Session EM+EN-FrM

Invited Paper EM+EN-FrM5
Development of Nitride Nanorod Light-emitting Diode Array

Friday, November 14, 2014, 9:40 am, Room 311

Session: Nitrides for LED and PV Device Applications
Presenter: Chih-Chung Yang, National Taiwan University, Taiwan, Republic of China
Authors: C.G. Tu, National Taiwan University, Taiwan, Republic of China
C.H. Liao, National Taiwan University, Taiwan, Republic of China
Y.F. Yao, National Taiwan University, Taiwan, Republic of China
C.Y. Su, National Taiwan University, Taiwan, Republic of China
H.S. Chen, National Taiwan University, Taiwan, Republic of China
W.H. Chen, National Taiwan University, Taiwan, Republic of China
C. Hsieh, National Taiwan University, Taiwan, Republic of China
H.T. Chen, National Taiwan University, Taiwan, Republic of China
Y.W. Kiang, National Taiwan University, Taiwan, Republic of China
C.-C. Yang, National Taiwan University, Taiwan, Republic of China
Correspondent: Click to Email
With the nano-imprint lithography and the pulsed growth mode of metalorganic chemical vapor deposition, a regularly-patterned, c-axis nitride nanorod (NR) light-emitting diode (LED) array of uniform geometry with m-plane core-shell InGaN/GaN quantum wells (QWs) is formed. To grow an NR with uniform cross-sectional size, in the pulsed growth mode, the sources of groups III and V are switched on and off alternatively with fixed supply durations. By growing a p-i-n core-shell structure, an InGaN/GaN QW NR LED array can be fabricated by depositing a conformal layer of GaZnO on the NRs for serving as the transparent conductor. The electrical property of such an LED array is comparable with that of a conventional planar LED. Besides, by varying the supply duration of group III source (TMGa) in the pulsed growth process, the NR cross section can be tapered for growing another section of NR of a different cross-sectional size. Based on this growth technique, a multiple-section GaN NR of changing cross-sectional size can be obtained. When InGaN/GaN QWs are deposited on the sidewalls of the NR, the indium contents and QW thicknesses are different in different sections of different cross-sectional sizes due to different strain relaxation conditions. In this situation, the emission wavelengths of the QWs from different sections are different, leading to the multiple-color emission of such an NR array. Such an emission behavior can be used for fabricating a phosphor-free white-light LED.