Characterizing Reverse-bias Electroluminescence of InGaN/GaN LEDs

Hsiang Chen1, Chyuan-Haur Kao2, Tien-Chang Lu3
1Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University, Puli, Taiwan, R.O.C.
2Department of Electronic Engineering, Chang Gung University, Kwei-Shan, Taiwan, R.O.C.
3 Department of Photonics Nationonal Chiao Tung Univers-ity, Hsinchu, Taiwan, R.O.C.
Corresponding e-mail:hchen@ncnu.edu.tw Phone: 886-49-2910960 ext 4909

Keywords: InGaN LED, Reverse Bias Luminescence, Electroluminescence, Leakage Current, Hot Carrier Induced Emission

Abstract

The reverse-bias operation of the InGaN LED device can shed a light on device reliability problems. Our goal is to use X-ray fluorescent (XRF) element analysis, 2D electroluminescence (EL) observations, and electrical measurements to visualize the current leakage and evaluate the fresh device performance. Hot electron- induced emissions due to a leakage current may be a
mechanism of the reverse-bias emission. The reverse-bias light emission is relevant to reliability problems because of its combination of optical characterization and electrical performance. Besides, a nondestructive screening method has been built to detect the leakage current path around the metal contact and evaluate fresh LED device quality.

Paper 11a.3.pdf