由於全球緩化的影響，發光二極體因其具有低汙染、低耗能與壽命長等特性，因此變得越來越普及。而目前發光二極體產業中，最普遍被使用的規範為IES LM-80-08，然其測試時間過於冗長，會延長產品的上市時程，造成發光二極體產業的研發障礙。
許多種應力形式可能影響發光二極體的光衰，例如溫度應力、電流應力與光應力。在本研究中，將提出在不同高溫應力但無輸入電流的情況，進行高功率發光二極體的加速老化試驗，並採用相同型號之一瓦氮化鎵發光二極體作為測試樣本。樣本包含白光發光二極體、藍光發光二極體與已去除透鏡之藍光發光二極體。其中白光發光二極體與藍光發光二極體之差別在於白光發光二極體有螢光粉，藍光發光二極體則無。隨著加速老化試驗進行記錄其光衰，再根據樣本之差異性，可分離出各光衰機制。
在深入了解樣本結構後，開始進行加速老化試驗，研究旨在（一）預估光衰模型，提供準確的壽命預估，（二）找出溫度應力在光衰老化試驗中的加速因子，（三）提出可用的方法以縮短目前至少必須進行6,000小時的IES LM-80-08與TM-21-11可靠度測試規範。由加速老化試驗結果發現，足夠高的溫度應力可以有效縮短發光二極體晶片的不穩定期。另外由本研究溫度應力加速因子所推算的預估壽命，和IES LM-80-08 與TM-21-11推算得到的預估壽命範圍皆相符。因此建議，現行發光二極體測試規範的溫度應力可以設定更為嚴苛，達到減少測試的時間，縮短產品上市時程，促進目前發光二極體產業的發展。

Due to the effect of global warming, light emitting diodes (LEDs) have become more and more popular in recent years with its advantages like low pollution, low power consumption, long operation lifetime and so on. However, the reliability test standard, IES LM-80-08, which is utilized mostly by LED industry costs too much time and prolonged the time-to-market. This situation can be regarded as an obstacle to the LED Research and development.
There are several types of stress may affect the LED degradation such as temperature stress, current stress, and optical stress. In this study, an accelerated aging test on high power LEDs at different high temperature stress without input current is proposed. A Gallium Nitride (GaN) based 1-W LEDs from the same series are chosen as test samples. The samples consist of white LEDs, blue LEDs and decapsulated blue LEDs. The difference between white LEDs, and blue LEDs is that white LEDs have phosphor but blue LEDs do not. The degradation of light output was detected during aging. According to the difference of samples, each degradation mechanisms can be separated.
The accelerated aging test started from an in-depth knowledge of the device structure, and aimed at (i) extrapolating the degradation model that can provide an accurate lifetime estimation, (ii) investigating acceleration factors (AF) of temperature stress in the aging test for degradation, (iii) proposing an available method to shorten the reliability test standards, IES LM-80-08 and TM-21-11, which cost 6,000 hours at least. The results of accelerated aging test show that a high enough temperature stress can effectively shorten the unstable period of LED chip. And the estimated lifetimes calculated from the AF of temperature stress in this study conform the span of lifetimes calculated from the IES LM-80-08 and TM-21-11. Therefore, it is recommended that the temperature stress of existing LED test standard can be set harsher. It would reduce testing time and shorten time-to-market and promote the current light-emitting diode industry.

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