導電布拉格反射鏡運用於高效率發光二極體之研究

本實驗研究著重於反射鏡的光學設計，利用高折射率(TNO)與低折射率(AZO)透明導電膜材料堆疊形成具導電性的布拉格反射鏡。分別運用於藍光LED與紅光LED，並實際做成元件量測。透明導電膜的製備都在室溫下進行鍍製並且在真空環境下退火370度。在藍光LED部分，以P-GaN/ITO/(TNO/AZO)^4/TNO的設計最佳並實際鍍製反射率可達約81%，電阻率可達到1.453?10-3Ω-cm。模擬P-GaN/ITO/(TNO/AZO)^10/TNO時，反射率約可以達到94%。在紅光LED的部分，P-GaP/ITO/AZO/DBR/Ag的反射鏡設計可以比單純使用銀作為反射鏡反射率來的較高，實際做成元件並量測軸向光強可以發現有效的由478.3mcd提升至508.8mcd，在表面粗化後更是由812mcd提升至902mcd，有效提升軸向光強約11%。

關鍵字

布拉格反射鏡；透明導電膜；高效率發光二極體

並列摘要

This study focused on optical design of reflectors and the films stacked by high refractive index material (TNO) and low refractive index (AZO) were deposited to make Distributed Bragg Reflectors. It was applied to blue LED, red LED and their device was made respectively for measurements. All transparent conductive oxide films were post-annealed at 370℃ in a vacuum. In blue LED part, the design of P-GaN/ITO/(TNO/AZO)^4/TNO was optimal, reflectivity of the coating reached approximately to 81%, and the conductive reflector showed a resistivity of 1.453?10-3Ω-cm. We used optic design of P-GaN/ITO/(TNO/AZO)^10/TNO to simulate coating with reflectivity approximately 94%. In red LED part, the reflectivity of P-GaP/ITO/AZO/DBR/Ag design is better than those using silver as the reflector. Actually we made device and measured the value of axial intensity, which increased from 478.3 mcd to 508.8 mcd. After surface roughening, the value of axial intensity increased from 812 mcd to 902 mcd. The design effectively enhanced axial intensity up to 11%.

並列關鍵字

transparent conductive oxide films ； high-efficiency Light-Emitting Diodes ； Distributed Bragg Reflectors

參考文獻

[2] G. B. Stringfellow, “ High brightness light emitting diode, “ Academic Press Inc.

Boston, pp. 149, 1997.

visible light-emitting diodes, Appl. Phys. Lett. 58, 1010 (1991).

green light-emitting diodes, Appl. Phys. Lett. 61, 1775 (1992).

High-brightness AlGaInP light emitting diodes; Proceedings of the IEEE Volume 85, Issue 11, NOV. 1997.

國際替代計量

導電布拉格反射鏡運用於高效率發光二極體之研究

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