飛秒雷射加工提升覆晶型發光二極體發光效率之研究

The Research of Femtosecond Laser Process Flip-Chip LEDs for Upgrading Lighting Efficiency

王弋豪(I-Hao Wang)

指導教授 ： 王祥辰

國立中正大學/工學院/光機電整合工程研究所/碩士(2013年)

摘要

在此研究中，我們利用飛秒雷射加工藍寶石基板，找出雷射劑量與藍寶石基板之間的關係。而我們找出雷射加工可誘發藍寶石週期性表面結構的參數為4mW、20pulses，並計算出直線加工也能產生表面微結構的雷射行徑速度為0.4mm/s。利用此參數大面積加工在高功率的覆晶型藍光發光二極體之上，找出雷射加工在覆晶型藍光發光二極體的藍寶石表面的覆蓋率與發光效率之間的關係，其結果顯示因為加工後的覆晶型藍光發光二極體的藍寶石表面有大量的黑色物質產生，雖然微結構確實能提升光的萃取率，但因為黑色物質大量擋住出光量，造成加工後的效率低於未加工的發光二極體。另一方面，發光效率還是會隨著覆晶型LEDs的表面結構覆蓋率上升而上升，代表在覆晶型LEDs的藍寶石表面做粗化提升光的萃取率還是有具有效果。

關鍵字

飛秒雷射 ； 發光二極體 ； 發光效率

並列摘要

In this study, we use femtosecond laser to process on sapphire substrate, and identify the relationship between laser dose and the laser ablation width on sapphire substrate. We find that laser process can induce sapphire period surface structure data is 4mW and 20 pulses, and calculating that laser still can form surface structure laser line scan velocity is 0.4mm/s. Laser large area process on high power flip-chip LEDs by using this data, we find the relationship between the nanostructure capping rate on LEDs surface and the LEDs light efficiency.
The result shows that because the LEDs have much black material after process. Although nanostructure indeed upgrade light extraction efficiency, but the black material block amount of light larger than the nanostructure extract light efficiency, so that form the light efficiency of process LEDs lower than non-process LEDs. On the other way, the light efficiency increase by the structure capping rate on LEDs, on behalf of the texture on LEDs surface to upgrade light extraction efficiency still have effect.

並列關鍵字

lighting efficiency ； femtosecond laser ； LED

參考文獻

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