本研究主要是以磁控式射頻濺鍍系統沉積摻雜鈮之二氧化鈦薄膜與銦錫氧化物薄膜，將其交互堆疊以製作具導電之分佈式布拉格反射鏡，並將其應用於藍光發光二極體，以增加其出光效率。摻雜鈮之二氧化鈦薄膜在氫氣環境下經溫度400oC熱處理30分鐘，可形成為透明導電薄膜，其電阻率約為1.12x10-3 Ω-cm。利用厚度分別為45 nm及60 nm之二氧化鈦與銦錫氧化物薄膜交互堆疊至13對時，則可使具導電之分佈式布拉格反射鏡於450 nm波段具有最高之反射率94.6 %。本研究將導電分佈式布拉格反射鏡結合金屬反射鏡製作成複合式反射鏡，應用於覆晶型藍光發光二極體上，藉此增強其藍光之出光效率。將分佈式布拉格反射鏡與單純金屬反射鏡及複合式反射鏡三種不同的反射鏡應用於傳統覆晶型發光二極體, 並對藍光發光強度與光輸出功率進行比較，可得知其藍光之強度明顯的變化，其相對應之藍光增強比例分別為20.5%、70.6%及95.8%，而光輸出功率比例各別為16.4%、43.1%及57.3%。

In this work, the niobium (Nb)-doped titanium dioxide (TiO2) films, referred as TNO films, and indium tin oxide (ITO) films were alternately deposited using magnetron radio frequency (RF) sputtering to form the distributed bragg reflector (DBR). The DBR was used to enhance the extraction efficiency of the GaN blue LEDs. The resistivity of the TNO films with thermal annealing in H2 ambience, at 400oC for 30 mins was 1.12x10-3 Ω-cm. The 45-nm-thick TNO film and 60-nm-thick ITO film were alternately deposited for 13 pairs to form the DBR with high reflectivity of 94.6 % at wavelength of 450 nm. DBR and metal reflector was combined to the hybrid reflector applied in the GaN blue LEDs to enhance the extraction efficiency. Comparison the luminous intensity and the light output power of the flip-chip GaN blue LEDs, the luminous intensity of the flip-chip GaN blue LEDs with DBR, metal reflector, and hybrid reflector enhanced to be 20.5%, 70.6%, and 95.8%, respectively. And the light output power enhanced to be 16.4%, 43.1%, and 57.3%, respectively.

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