Optical degradation mechanisms of mid-power white-light LEDs in LM-80-08 tests

Huang, Jianlin; Golubović, D.S.; Koh, Sau; Yang, Daoguo; Li, Xiupeng; Fan, Xuejun; Zhang, G.Q.

doi:10.1016/j.microrel.2015.09.008

Cited by 12 publications

(10 citation statements)

References 32 publications

(37 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From 3000 to 6000 h, it is found that chip-level degradation has been triggered. This degradation mechanism has been verified by comparing the output power of the blue lights of several nonstressed samples and stressed samples [29]. In order to gain reliable comparison, the silicone encapsulant was removed prior to optical measurement.…”

Section: Validation and Applicationmentioning

confidence: 92%

See 1 more Smart Citation

Degradation Mechanism Decoupling of Mid-Power White-Light LEDs by SPD Simulation

Huang

Golubović²,

Koh

et al. 2016

IEEE Trans. Electron Devices

Self Cite

View full text Add to dashboard Cite

A degradation mechanism analysis methodology is proposed for the mid-power white-light LED packages in this paper. Based on the degradation data obtained from a series of aging tests that are performed on the individual packaging material, the degradation kinetics of lumen output and spectral power distribution of the LED packages are investigated using optical simulation. As a result, although the reflectivity of the packaging materials decreased severely for the blue lights (i.e., 450 nm), the simulation showed that lights at this wavelength were little absorbed in the LED package. More specifically, it is found that: 1) the degradation of the blue lights is mainly due to blue chip deterioration, while rarely affected by the degradation of the silicone encapsulant and other packaging materials; 2) the degradation of the down-converted lights is significantly attributed to the degradation of the blue chips, the phosphors, the lead frames, and the package housing; and 3) the degradation of the silicone encapsulant contributes about 1.35% to the total lumen degradation within 168 h, while has no more contribution to the lumen degradation with further aging duration. The simulation results have been validated by experiments and successfully applied to the degradation mechanism analysis of LED packages in LM-80-08 tests.Index Terms-Light-emitting diodes (LEDs), lumen degradation, reliability, spectral power distribution (SPD).

show abstract

Section: Validation and Applicationmentioning

confidence: 92%

“…This degradation mechanism, combining with the package-level degradation mechanisms which are induced by either degradation of the lead frames or of the package housing, contributes to the lumen degradation of the LED packages. A detailed degradation mechanism analysis has been performed in [29].…”

Section: Validation and Applicationmentioning

confidence: 99%

Degradation Mechanism Decoupling of Mid-Power White-Light LEDs by SPD Simulation

Huang

Golubović²,

Koh

et al. 2016

IEEE Trans. Electron Devices

Self Cite

View full text Add to dashboard Cite

show abstract

“…They conclude that the luminous flux of the LEDs show a steady and slow depreciation but no proper statistical analysis was performed on their measured data. Huang et al [15,16,17] investigated the degradation mechanisms of mid-power white-light LEDs. In their studies, a modified Wiener process was employed for the modeling of the LED devices' degradation, following the earlier work of Tsai et al [18].…”

Section: Current Agreed Methodsmentioning

confidence: 99%

Lumen maintenance predictions for LED packages

Driel

Schuld²,

Jacobs

et al. 2016

Microelectronics Reliability

View full text Add to dashboard Cite

Commercial claims for LED-based products in terms of lumen maintenance are fully based on TM-21 extrapolations using LM-80 data. This paper indicates that there may be a risk in doing this as TM-21 only relies on the behavior of the average LED degradation, instead of taking into account the degradation of all individual LEDs. Therefore, we propose a more profound statistical analysis in order to make the appropriate step from TM-21 extrapolation to lumen maintenance on a product level. This is needed as some commercial claims are based on 10 years of warranty and some service bids provide periods of 20 to 25 years of operation. This paper reviews the different approaches currently available to perform lumen maintenance extrapolations. We propose a new method to analyze and extrapolate LM-80 data using a more profound statistical approach. Highlights The main highlights of the presented research are: • A new statistical method to extrapolate LM-80 data • The method outperforms the currently available ones as it is statistically founded • Five cases were executed and benchmarked with the TM-21 method • A full statistical acceleration model is now available for lifetime assessment of LEDs

show abstract

“…They conclude that the luminous flux of the LEDs shows a steady and slow depreciation, but no proper statistical analysis was performed on their measured data. Huang et al [28][29][30] investigated the degradation mechanisms of mid-power white-light LEDs. In their studies, a modified Wiener process was employed for the modeling of the LED devices' degradation, following the earlier work of Tsai et al [31].…”

Section: Lumen Maintenancementioning

confidence: 99%

Health Monitoring for Lighting Applications

Driel

Middelburg

Mansouri

et al. 2019

Sensor Systems Simulations

View full text Add to dashboard Cite

The history of reliability as we know it now goes back to the 1950s, when electronics played a major role for the first time [1,2]. Now, 70 decades later, the electronic industry is facing a continuous increase of early and wear-out failures with accompanying consequences. Figure 13.1 depicts the struggle for the different high-tech industries, ranging from harsh environment suitability to long lifetime and warranty coverage. Nowadays, products with high failure rates are logged on the web leading to bad reputation for a company. In many ways, reliability is part of everyday life and part of consumer expectations. The word reliability is extensively used by the general public and the technical community, as illustrated by the following: there are over 3000 published books whose title or keywords contain the word reliability; the web of science lists some 10,000 technical papers with "reliability" as a keyword (since 1973); and the popular search engine Google lists over 12 million occurrences of "reliability" on the world wide web.Solid state lighting applications are now at the doorstep of massive market entry [3,4]. The penetration will grow most rapidly in the street and roadway and general service submarkets in terms of the percentage of total lumen-hour sales [5][6][7]. Scenarios estimate the expected future adoption of LEDs based on historical data

show abstract

Optical degradation mechanisms of mid-power white-light LEDs in LM-80-08 tests

Cited by 12 publications

References 32 publications

Degradation Mechanism Decoupling of Mid-Power White-Light LEDs by SPD Simulation

Degradation Mechanism Decoupling of Mid-Power White-Light LEDs by SPD Simulation

Lumen maintenance predictions for LED packages

Health Monitoring for Lighting Applications

Contact Info

Product

Resources

About