本研究目的在於利用化學氣相沉積的程序變化模式，尋找在低溫下成長低電阻率且具有光學散射特性之粗糙表面氧化鋅鎵薄膜，最終目標在用來取代氧化銦錫當作為藍光發光二極體的透明導電接觸層。
考慮鎵源先驅物-三乙基鎵不易在200℃以下裂解，我們嘗試利用遠距式電漿輔助解離鎵源氣體，再通入二乙基鋅/水之反應系統來沉積薄膜。結果顯示，以此方法在基材溫度為146℃所成長出的薄膜具有粗糙表面，且在455~475 奈米光波段的霧度最高可達20%，但是電阻率卻高達102 Ω∙cm。推測乃因為以遠距式電漿獨立供給的鎵源氣體在進入腔體前即反應而失去活性。
另外，我們發現使用傳統的低壓化學氣相沉積法，令獨立供給的三乙基鎵和預先與水混合的二乙基鋅來進行競爭反應時，可在130℃的低溫及適當的三乙基鎵/二乙基鋅及水/二乙基鋅流量比下生成電阻率為2.61×10-3 Ω∙cm，且表面粗糙(光波段為455~475 奈米區間的霧度約為11%)的摻鎵氧化鋅薄膜。

The aim of this study is using various CVD (chemical vapor deposition) methods to synthesize Ga-doped ZnO thin films with low electrical resistivity and textured surface for light-scattering. The final purpose is to substitute ITO applied as the material of transparent conductive layer above p-type GaN layers for GaN-based LEDs.
Considering that triethylgallium (TEGa) is not easily to decompose under 200℃, we tried to use remote plasma-assisted dissociation of TEGa and to let it to react with DEZn/H2O-LPCVD reaction system. The synthesized films showed rough surface structures with 20% haze at around 460 nm. However, the films resistivity was relatively high (>102Ω∙cm). Another way to use traditional LPCVD but supplying TEGa separately into a reaction zone where DEZn has already met with H2O has also been tried. The result showed that a under low substrate temperature of 130℃, Ga-doped ZnO films did form with a lowest electrical resistivity value of 2.61×10-3 Ω∙cm and a haze value of 11% (near 460 nm). A possible mechanism was proposed to explain this phenomenon.

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