Paper Info
Title
High temperature electro-optical degradation of InGaN/GaN HBLEDs
Abstract
This paper presents a study of the high temperature degradation of high brightness light emitting diodes (HBLEDs) on gallium nitride. Two different families of devices, from two leading manufacturers, have been submitted to thermal stress: during treatment, the optical and electrical characteristics of the devices have been analyzed. Degradation modes detected after stress have been (i) operating voltage increase, (ii) output power decrease, (iii) modifications of the spectral properties. The degradation of the electrical and optical characteristics of the devices were found to have different kinetics: this fact indicates that optical power (OP) loss is not strongly related to the degradation of the electrical parameters of the LEDs. On the other hand, spectral analysis indicated that OP loss is strongly related to the decrease of the phosphors-related yellow emission band. Microscopic analysis showed that this effect can be ascribed to the carbonization of the package and phosphorous material. A degradation of the transparency of the top-side ohmic contact has been also detected after stress: these mechanisms are thought to be responsible for the detected OP decrease. OP decay process has been found to be thermally activated, with activation energy equal to 1.5eV.
Year
DOI
Venue
2007
10.1016/j.microrel.2007.07.081
Microelectronics Reliability
Keywords
Field
DocType
light emitting diode,thermal stress,activation energy,kinetics,ohmic contact
Gallium nitride,Optical power,Chemistry,Electronic engineering,Stress (mechanics),Degradation (geology),Light-emitting diode,Optoelectronics,Brightness,Activation energy,Ohmic contact
Journal
Volume
Issue
ISSN
47
9
0026-2714
Citations 
PageRank 
References 
12
3.20
3
Authors
7
Name
Order
Citations
PageRank
M. Meneghini12310.17
L. Trevisanello2199.01
C. Sanna3123.20
G. Mura4398.68
M. Vanzi58933.52
G. Meneghesso65222.83
E. Zanoni72911.67