Investigation on Thermal Characteristics of Lamp with High-power LEDs Packaging

With the development of high power LED technology, junction temperature as a key factor constrains the performance and the service life of LED, and the main parameter of junction temperature is thermal resistance. Therefore, how to measure the thermal resistance of high power LED quickly and accurately plays an important part in improving the performance and the service life of LED. In this paper the accurate and fast measurement equipment was applied to study the thermal characteristics of high power LED. The forward-voltage based method was conducted to measure the junction temperature of high power. Then, support vector regression (SVR) combined with genetic algorithm (GA) for its parameter optimization, was proposed to establish a model to predict the thermal resistance of high power LED. The prediction performance of GA-SVR was compared with those of BPNN model. The result demonstrated that the estimated errors GA-SVR models, such as Mean Absolute Relative Error (MARE) and Root Mean Squared Errors (RMSE), all are smaller than those achieved by the BPNN applying identical samples.

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Effects of humidity on the electro-optical-thermal characteristics of high-power LEDs

2016 IEEE 18th Electronics Packaging Technology Conference (EPTC) ◽

10.1109/eptc.2016.7861576 ◽

2016 ◽

Author(s):

T. K. Law ◽

Fannon Lim ◽

Y. Li ◽

J. W. Ronnie Teo ◽

Sophia Wei

Keyword(s):

High Power ◽

Thermal Characteristics

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Numerical investigation on thermal characteristics of GaN HFETs for high power applications

2006 Asia-Pacific Microwave Conference ◽

10.1109/apmc.2006.4429456 ◽

2006 ◽

Cited By ~ 1

Author(s):

Jianfeng Xu ◽

Wen-Yan Yin ◽

Junfa Mao

Keyword(s):

Numerical Investigation ◽

High Power ◽

Thermal Characteristics

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Thermal Characteristics Analysis of Die Attach Layer Based on Time-Constant Spectrum for High-Power LED

IEEE Transactions on Electron Devices ◽

10.1109/ted.2015.2474395 ◽

2015 ◽

Vol 62 (11) ◽

pp. 3715-3721 ◽

Cited By ~ 14

Author(s):

Wei Lai ◽

Xianming Liu ◽

Weimin Chen ◽

Xiaohua Lei ◽

Xueying Cao

Keyword(s):

Time Constant ◽

High Power ◽

Thermal Characteristics ◽

Die Attach ◽

High Power Led ◽

Characteristics Analysis

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Thermal Characteristics of High-Power LED Packages with Dissipation Film

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.397-400.1767 ◽

2013 ◽

Vol 397-400 ◽

pp. 1767-1771

Author(s):

Cheng Yi Hsu ◽

Yu Li Lin

Keyword(s):

High Power ◽

Diamond Film ◽

Light Emitting Diodes ◽

Light Emitting Diode ◽

Thermal Characteristics ◽

Large Change ◽

Junction Temperature ◽

Conduction Model ◽

Element Analysis ◽

Light Emitting

A simple, fast, and reliable characterization method for measuring junction temperature (Tj) on high power GaN-based light emitting diodes (LED) was presented in this study. Thermal characteristics of high power Light-emitting-diode have been analyzed by using a three-dimensional thermal conduction model. Maximum operation temperature has also been calculated. The induced thermal behaviors of the best package processes for LED device with diamond film were investigated by finite element analysis (FEA) and by experimental measurement. The large change of forward operation voltage with temperature in light emitting diodes is advantageously used to measure junction temperature. Using this method, junction temperature (Tj) of LED under various structures and chip mounting methods was measured. It was found that the junction temperature can be reduced considerably by using diamond film substrates to replace sapphire substrate. In this study, the junction temperature can be decreased by about 14.3% under 1.5W power and decreased by about 15.9% under 1W power for 1mm square die. The thermal resistance (RT) can be measured to be 14.8°C/W under 1.5W power and 16.6°C/W under 1.W power.

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High-Speed and High-Power 940 nm Flip-Chip VCSEL Array for LiDAR Application

Crystals ◽

10.3390/cryst11101237 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1237

Author(s):

Kuo-Bin Hong ◽

Wei-Ta Huang ◽

Hsin-Chan Chung ◽

Guan-Hao Chang ◽

Dong Yang ◽

...

Keyword(s):

High Power ◽

High Speed ◽

Flip Chip ◽

Maximum Output Power ◽

Thermal Characteristics ◽

Cavity Surface ◽

Maximum Output ◽

Two Samples ◽

Vertical Cavity Surface ◽

Surface Emitting Laser

In this paper, we demonstrate the design and fabrication of a high-power, high-speed flip-chip vertical cavity surface emitting laser (VCSEL) for light detection and ranging (LiDAR) systems. The optoelectronic characteristics and modulation speeds of vertical and flip-chip VCSELs were investigated numerically and experimentally. The thermal transport properties of the two samples were also numerically investigated. The measured maximum output power, slope efficiency (SE) and power conversion efficiency (PCE) of a fabricated flip-chip VCSEL array operated at room-temperature were 6.2 W, 1.11 W/A and 46.1%, respectively. The measured L-I-V curves demonstrated that the flip-chip architecture offers better thermal characteristics than the conventional vertical structure, especially for high-temperature operation. The rise time of the flip-chip VCSEL array was 218.5 ps, and the architecture of the flip-chip VCSEL with tunnel junction was chosen to accommodate the application of long-range LiDAR. The calculated PCE of such a flip-chip VCSEL was further improved from 51% to 57.8%. The device design concept and forecasting laser characteristics are suitable for LiDAR systems.

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