Characterizations of Low-Temperature Electroluminescence from n-ZnO Nanowire/ p-GaN Light Emitting Diodes

Tzu-Chun Lu,1 Min-Yung Ke,1 Sheng-Chieh Yang,1 Yun-Wei Cheng,1 Liang-Yi Chen,1 Guan-Jhong Lin,1
Yu-Hsin Lu,2 Jr-Hau He,1 Hao-Chung Kuo,2 and JianJang Huang1,*
1Graduate Institute of Photonics and Optoelectronics, National Taiwan University, 1,
Roosevelt Road, Sec. 4, Taipei, 106 Taiwan
Phone:+886-2-3366-3534, Fax:+886-2-2367-7467, E-Mail: jjhuang@cc.ee.ntu.edu.tw
2Department of Photonics, National Chiao Tung University, Hsinchu 300, Taiwan

Keywords: UV LED, ZnO nanowire, low-temperature electroluminescence

Abstract

Low temperature electroluminescence (EL) from a ZnO nanowire light emitting arrays is reported. By inserting a thin MgO current blocking layer in between ZnO nanowire and p- GaN, high purity UV (ultra-violet) light emission at wavelength 398nm was obtained. As the temperature is decreased, contrary to the typical GaN based light emitting didoes (LEDs), our device shows a decrease of optical output intensity. The results are associated with various carrier tunneling processes and frozen of MgO defects.

Paper 13.9.pdf