應用全方位反射鏡提高氮化鎵系發光二極體光效之研究與探討

Enhancement in Light Output of GaN-based Light-Emitting Diodes with Omni-Directional Reflectors

鄭政欣(Cheng-Hsin Cheng)

指導教授 ： 陳隆建

國立臺北科技大學/電資學院/光電與能源產業研發碩士專班/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00577

摘要

本研究係利用射頻反應式磁控濺鍍法（radio-frequency magnetron sputtering）沉積TiO2 / SiO2 / Ag全方位反射鏡（Omni-Directional Reflectors，ODRs）在氮化鎵系發光二極體（GaN-based LEDs）藍寶石基板的背面，避免光從元件的背面耗損，以提升GaN-based LEDs發光效率。
實驗以固定濺鍍功率、氬氣(Ar)流量和時間，在玻璃基板和GaN-based LEDs藍寶石基板的背面上分別沉積1、3、5對TiO2 / SiO2 / Ag ODRs測試樣品，沉積的時間及厚度分別為TiO2：110 minutes/50nm、SiO2：20 minutes/80nm、Ag：3 minutes/75nm。反射光譜量測沉積於玻璃基板的1、3、5對TiO2 / SiO2 / Ag ODRs於大約460nm表現出反射率高達85~96%，顯示TiO2 / SiO2 / Ag ODRs能有效反射GaN-based LEDs的發光波段。
最後於室溫下量測GaN-based LEDs的L-I光電特性，在20mA以5對的TiO2 / SiO2 / Ag ODRs光輸出功率與傳統的GaN-based LEDs比較增加約61%，證明TiO2 / SiO2 / Ag全方位反射鏡能有效提升GaN-based LEDs發光效率。

關鍵字

全方位反射鏡 ； 氮化鎵系發光二極體 ； 射頻反應式磁控濺鍍法

並列摘要

In this study, TiO2/SiO2/Ag Omni-Directional Reflectors（ODRs）were deposited on the backside of the sapphire substrate of the GaN-based lighting-emitting diodes (LEDs) by radio-frequency reactive magnetron sputtering deposition, to avoid loss of light from the back of components to enhance the efficiency of light emitting diodes.
This experiment is based on sputtering power, Ar air flow, and time. Deposit 1, 3, and 5 pairs of TiO2/SiO2/Ag ODRs on the backside of the sapphire substrates of the GaN-based LEDs and the glass substrates to make it become an experimental sample. The exact time of the deposits and the thickness should be TiO2：110 minutes/55nm、SiO2：20 minutes /80nm、Ag：3 minutes/75nm. The reflect spectrum measure the deposition on the glass substrates of 1, 3, and 5 pairs of TiO2/SiO2/Ag ODRs and they are about 460nm. It shows that the reflection is about 85~96%. It shows that the TiO2/SiO2/Ag ODRs have great effect on the reflection of the GaN-based LEDs luminescence band.
The last step is to measure the L-I of the GaN-based LEDs’s electric quality. Use five pairs of TiO2 / SiO2 / Ag ODRs and traditional GaN-based LEDs which have been increase about 61% on the 20mA. This proves that the TiO2 / SiO2 / Ag can improve GaN-based LEDs light efficiency.

並列關鍵字

Omni-directional reflectors ； GaN-based light-emitting diodes ； radio- frequency magnetron sputtering

參考文獻

[10] 何宗彧，以背鍍分佈式布拉格反射鏡提升發光二極體發光效率之研究，國立台灣大學光電工程研究所，碩士論文。(2009), pp.24-26

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