為了要增加光輸出功率，我們使用三種不同電流擴散層，薄的雙層金屬鎳金、氧化鋅鋁和銦錫氧化物， Sputter成長ITO和AZO以及E-GUN成長ITO，最低電阻率都能達到2×10-4Ω-cm。將這四種薄膜分別鍍在玻璃上，再以U-4100 Spectrophotometer來量測穿透率；鎳金、氧化鋅鋁和銦錫氧化物的穿透率在波長456nm分別為53%、74%、68.7%(Sputter)和90.2%(E-Gun)。因此選擇E-Gun所成長的銦錫氧化物來做為元件的電流擴散層，由於銦錫氧化物對於P-GaN無法形成良好的歐姆接觸，於是選用高功函數的鎳金屬來形成歐姆接觸，利用傳輸線模型（TLM）分析，我們可以找出Ni/Au和Ni/ITO在P-GaN歐姆接觸的最佳製程參數。
我們將藍光晶粒以SMD(表面黏著)的方式進行封裝，晶粒放置於鍍銀的基座上，杯面為120ﾟ夾角，使用折射係數為1.5的矽膠封裝，導致低的臨界角損失和Fresnel損失。

In order to increase output power, we used three differentt kinds of current spreading layer ,thin bilayer metal Ni/Au, AZO and ITO. ITO and AZO were deposied by sputter and ITO was growed by E-Gun, their lowest resistance could all reach about 2×10-4Ω-cm2. We deposited the four thin films on glass and measure the transmittance by U-4100 Spectrophotometer. The transmittance of Ni/Au, AZO and ITO at wavelength 456nm are about 53%、74% 、68.7% (Sputter) and 90.2% (E-Gun). So we choose ITO deposited by E-Gun as our device's current spreading layer. Owing to ITO can't form good ohmic contact on P-GaN, we use high work function metal nickel to form ohmic contact. Taking advantage of transmission-line-model to analyze, we could find the best process parameter of ohmic contact on P typed GaN for Ni/Au and ITO.
We took the LED die to be packaged by SMD mode. Dies were attached on substrate electroplated silver. And the cup face’s angle is 120ﾟ. We used organic silicon resin whose refractive index is 1.5 to encapsulate results in low critical angle loss and Fresnel loss.

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