發光二極體與傳統的照明燈泡比較，二極體具有多項優點如：元件壽命長、低電流、低驅動電壓的省電特性、體積小、對環境較環保、反應速度快等，可以很廣泛的應用在通訊、電子、汽車、光電顯示等各種新興相關產業。
發光二極體慢慢取代白熾燈，熒光燈，金屬鹵化物燈，普通照明，汽車信號燈，大型液晶顯示器，汽車頭燈等照明。發光二極體取代傳統燈具每一年將節省157核電廠生產電力。因此，固態照明將是一個為生活用照明的趨勢。
在發光二極體要成為廣泛運用的照明設備前，必須要在其發光效率上有所提升才行，隨著效率的提升，具有高亮度的發光二極體才有被應用於照明光源的價值，並足以跨足各光源市場領域。於發光效率得提升有多種方法，如：表面粗化、特殊表面圖形、光子晶體、將側面做成斜面或磊晶前藍寶石基板圖樣化等，其最終目的皆在改善外部及內部量子效率。
本論文針對圖案化藍寶石基板開發進行研究，首先利用日本Nikon NSR系列步進式曝光機於藍寶石基板上進行黃光圖形定義，接著利用韓國Maxis電感耦合電漿蝕刻機(ICP-RIE)進行圖形蝕刻，其中調整蝕刻機相關參數以獲得不同高度寬度的圖案化藍寶石基板為本次研究的第一階段重點。
第二階段，因藍寶石基板(Sapphire)與氮化鎵(GaN)磊晶層間折射率差異過大，導致出光效率不佳，故當於藍寶石基板(Sapphire)與氮化鎵(GaN)磊晶層間加入另一介質，應會提高整體發光效率，因此，在本次開發研究中我們選擇SiO2作為介質，利用第一階段的蝕刻經驗來協助進行二氧化矽圖案畫藍寶石基板(SiO2 PSS)製程的開發。

Light - Emitting Diode (LEDs) is a Solid-state Opto-electronic semiconductor devise has advantages of small volume, low power consumption, long lifetime, compressible and environment protection. LEDs can be used more applications in communications, electronics, automotive, electro-optical display a variety of emerging-related industries.
LEDs slowly replace of incandescent, fluorescent, Hg and Xe lamps for general lighting、signal lights of cars, back lighting in large liquid-crystal displays, vehicle head lamps and so on. The research reported that LEDs replace the traditional Lamps will save 157 Nuclear Power Plants produced electric power per one year. So, LEDs will be a trend for life lighting using.
Before the light-emitting diode lighting equipment to become widely used, must be improved luminous efficiency. When LEDs have improved efficiency, the high brightness LEDs will be applied to the value of the illumination light source, and LEDs can be into the light source and market segments. For increasing light extraction efficiency on LEDs devices, many method researches reported such as using Epitaxial Lateral Overgrowth (ELOG), Textured Surface on p-type GaN by etching, Maskless Epitaxial Lateral Overgrowth, Air-bridge Epitaxial Lateral growth (ABLEG), Photonic Crystal, AlN buffer layer and Patterned sapphire substrate (PSS).
This thesis focuses on the development of patterned sapphire substrates research. First, we used Japan Nikon NSR series Stepper to exposure and defined PR graphics on sapphire substrate. Then we used Korea Maxis inductively coupled plasma etcher (ICP-RIE) to etch sapphire graphic, which adjust the the etching machine parameters to obtain patterned sapphire substrates of different height and width as the first stage of the research focuses on.
In second stage, because the differences of refractive index between the sapphire substrate and the gallium nitride epitaxial layer (GaN) are too large, so LEDs light are inefficient. When the sapphire substrate (Sapphire) and the gallium nitride epitaxial layer (GaN) is added another medium, that should improve the overall luminous efficiency. Therefore, in the present development study, we chose SiO2 as a medium. And we use the etching experience of first stage to help development the silicon dioxide patterned sapphire substrate (SiO2 PSS).

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