近年來，隨著環保意識的抬頭，發光二極體在固態照明中扮演著極為重要的角色。為了要將發光二極體廣泛地運用於日常照明中，其亮度與成本問題仍是有待解決的！本論文中，分別在垂直式發光二極體與水平式發光二極體的製程上做些微的改變以增加光取出率。就垂直式發光二極體而言，做一個保護牆在反射鏡的外圍以防止在製程中的酸、鹼溶液對於反射鏡的侵蝕，進而維持反射鏡金屬的反射率及阻值，其亮度可以提升59.78%。除此之外，應用不同的製程步驟於垂直式發光二極體中以減少強酸運用於製程中的機會，將對於反射鏡傷害盡量減小。就水平式發光二極體而言，將n type及p type的電極金屬種類由Cr/Pt/Au變成Cr/Pt/Ag。以銀取代金的好處有以下三點：成本較低、在藍光發光波段之反射率較高以及電阻係數較低。這些優點使得以Cr/Pt/Ag當n type及p type電極運用於大尺寸與小尺寸的發光二極體亮度分別提升16.63%及12.32%，而順向電壓分別降低0.06伏特及0.18伏特。

With the awakening of environmental protection, light emitting diodes play an important role in the solid lighting. To employ the light emitting diodes into general lighting use, the problems that should be solved are output light intensity and cost. In this thesis, there are some methods on the fabricating process for the vertical and lateral light emitting diodes respectively to increase the light output intensity. For vertical light emitting diodes, side walls are used around reflector to prevent reflector from being deteriorated by the acid and alkaline solutions. Then, this additional protection can maintain the reflectivity and resistance of metals for reflector. The light output intensity is 59.78% higher with the light emitting diodes with the side walls as protection of reflector. Moreover, to decrease the possibility of using strong acid solutions into the fabricating process, a different fabricating procedure is applied to minimize the damage induced to the reflector. For lateral light emitting diodes, the materials of metals for n and p pads, Cr/Pt/Au, are replaced with Cr/Pt/Ag. There are three advantages for replacing gold with silver: lower cost, higher reflectivity in the spectrum of blue light, and lower resistivity. With these advantages, the light output intensities for the large-sized and small-sized light emitting diodes with Cr/Pt/Ag as n and p pads are 16.63% and 12.32% higher respectively, and the forward voltages are 0.06 volts and 0.18 volts lower.

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