LED發光二極體暫態熱阻量測分析

Transient Thermal Resistance study in Light Emitting Diode

曾俊瑜(Jyun-Yu Zeng)

指導教授 ： 康尚文

淡江大學/工學院/機械與機電工程學系碩士班/碩士(2012年)

https://doi.org/10.6846/TKU.2012.01244

摘要

在全球能源越來越缺乏的環境下，環保意識的抬頭，隨著綠色能源與節約能源備受重視，世界興起一股綠色能源風暴。因此，具有耗電量小、使用壽命長、環保、顏色豐富、高亮度的發光二極體(Lighting Emitting Diode; LED)在近年來有逐步取代傳統光源的趨勢，為此，LED之散熱構裝影響更為重要，需要更深入的探討。
本論文旨在使用T3Ster系統做測暫態熱阻量測與分析，元件大小為1.4cm×1.4cm，厚度為0.2cm，晶粒大小為0.12cm×0.12cm，因T3Ster在量測二極體之特性有其獨特優點，包括量測時間快速、準確、並能於量測開始1微秒即開始紀錄資料，之後建立LED溫度敏感參數(Temperature Sensitive Parameter；TSP)曲線並使用其後處理程式T3Ster
Master做結構方程式的轉換，得知LED構裝之熱容比熱阻圖，介而推估每一層熱阻大小，並分析其在不同晶粒間距以及不同操作電流下熱阻的趨勢分布。
最後，本文藉由改變操作電流大小、晶粒數量、晶粒距離、以及電流方式來比較其中熱阻大小之影響，並得知晶粒不可太靠近散熱基板邊緣，反而會造成散熱面積不足而影響整體熱阻。

關鍵字

發光二極體 ； 暫態熱阻量測 ； 熱阻 ； 溫度敏感參數

並列摘要

From the environment of decreasing energy, energy saving has become more and more important issue. LED (Lighting Emitting Diode), which has various advantages, such as less power consumption, long lifespan, environmentally friendly, variegated colors and high brightness has replace traditional light sources step by step. Thus, heat dissipation of LED package is the top issue, and need to do more in-depth discussion.

This study presents a methodology for investigating the heat dissipation of the LED package. Using T3Ster measurement system to get the thermal resistance data. The aluminum plate dimension of device in this study is 1.4cm x 1.4cm x 0.2cm and the LED chip dimension of device is 0.12cm x 0.12cm, due to T3Ster has many unique advantages in measuring diode the characteristics, including accuracy, measure time is fast and can start measuring in 1 microsecond. Then get the LED package TSP (Temperature Sensitive Parameter) curve and Rth-Cth graphic from the T3SterMaster software to evaluate every part of package's thermal resistance. According to the data that we get and analysis Rth trends distribution in different chip distance and working power.

Finally, in this study, we analysis the value of Rth by change of current value, number of LED chip, chip to chip distance and current mode to compare the different. Knowing that chip can't be too close to the edge of the heat dissipation substrate otherwise will lead to affect total Rth cause the insufficient cooling area.

並列關鍵字

LED ； T3Ster ； Thermal Resistance ； TSP

參考文獻

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