Slanted n-ZnO/p-GaN nanorod arrays light-emitting diodes grown by oblique-angle deposition
Yi-Lun Chuang1*, Yung-Chi Yao1, Zu-Po Yang2, Fang-Yuh Lo3, Jhih-Jhong Siao1, Zhong-Han Xie1, Tai-Yuan Lin4, Jinn-Kong Sheu5, Ya-Ju Lee1
1Institute of Electro-Optical Science and Technology, National Taiwan Normal University, Taipei, Taiwan
2Institute of Photonic Systems, National Chiao-Tung University, Tainan, Taiwan
3Department of Physics, National Taiwan Normal University, Taipei, Taiwan
4Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung, Taiwan
5Department of Photonics, National Cheng Kung University, Tainan, Taiwan
* presenting author:Li-Yun Chuang,
High-efficient ZnO-based nanorod array light-emitting diodes (LEDs) were grown by an oblique-angle deposition scheme. Due to the shadowing effect, the inclined ZnO vapor-flow was selectively deposited on the tip surfaces of pre-fabricated p-GaN nanorod arrays, resulting in the formation of nanosized heterojunctions. The LED architecture composed of the slanted n-ZnO film on p-GaN nanorod arrays exhibits a well-behaving current rectification of junction diode with low turn-on voltage of 4.7 V, and stably emits bluish-white luminescence with dominant peak of 390 nm under the operation of forward injection currents. In general, as the device fabrication does not involve passivation of using a polymer or sophisticated material growth techniques, the revealed scheme might be readily applied on other kinds of nanoscale optoelectronic devices.

Keywords: Znic Oxide (ZnO), oblique-angle deposition, nanorod arrays, light-emitting diode (LED)