利用快速熱退火在砷化鎵基板上成長p型氧化鋅

Growth of p-type ZnO on GaAs Sbstrate Using Rapid Thermal Annealing

吳珍汝(Chen-Ju Wu)

指導教授 ： 雷伯薰

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2011年)

摘要

氧化鋅，一個II-VI族的化合物半導體，在室溫下能隙約為3.37eV，且有很大的激子束縛能，約為60meV，近年來成為非常吸引人的材料，特別是在紫外光段短波長的發光二極體及雷射裝置。
本研究是使用電漿輔助有機金屬化學氣相沉積法在砷化鎵基板上成長氧化鋅薄膜，再利用快速熱退火製程將基板中的砷原子擴散進入n型氧化鋅薄膜中，使其轉變成為p型氧化鋅薄膜，我們分為兩個主題，第一個是通氮氣，另一個是通氧氣進行快速熱退火，探討不同快速退火的溫度及持溫時間對氧化鋅薄膜特性、光電特性與表面型態之影響。我們證實快速熱退火有助於砷原子在擴散時，會進入適當的位置。在成長氧化鋅溫度為185℃，RTA 425℃ 通入氮氣，由 n 型轉 p 型，電洞濃度為 2.38 × 1020 cm-3，電阻率為 6.88 × 10-4 Ωcm，移動率為 12.7 cm2/Vs，而在成長氧化鋅溫度為190℃，RTA 450℃ 通入氧氣，由 n 型轉 p 型，電洞濃度為 3.07 × 1020 cm-3，電阻率為 7.31 × 10-4 Ωcm，移動率為 24.1 cm2/Vs。

關鍵字

電漿 ； 有機金屬化學氣相沈積法 ； p型氧化鋅 ； 砷化鎵 ； 快速熱退火

並列摘要

Zinc oxide (ZnO) is one of II-VI compound semiconductor with a wide band gap of 3.37 eV at room temperature and a large excition binding energy of 60meV, which makes it be an attractive material recently, especially in the application of blue and ultraviolet light-emitting diodes and laser.
In this thesis, the ZnO film growth on gallium arsine (GaAs) substrate was prepared by double plasma-enhanced metal-organic chemical vapor deposition system (DPEMOCVD). Then, the as-grown ZnO film was treated with rapid thermal process by rapid thermal annealing. With the thermal energy, the arsenic atoms can diffuse into the ZnO film as a p-type dopant. Two subjects were investigated in this thesis, including annealing in oxygen and nitrogen ambient. The effects of annealing temperature and time related to the optoelectronic characteristics of ZnO film and surface structure were investigated in this thesis in oxygen and nitrogen. The experiment results indicated that under the condition of grows substrates temperature at annealing temperature of 425℃ and annealing time of 1 minute in nitrogen ambient, the hole concentration, carrier mobility, and resistivity is 2.38 × 1020 cm-3, 6.88 × 10-4 Ωcm, and 12.7 cm2/Vs, respectively. In other word, under the condition of grows substrates temperature at annealing temperature of 450℃ and annealing time of 1 minute in oxygen ambient, the hole concentration, carrier mobility, and resistivity is 3.07 × 1020 cm-3, 7.31 × 10-4 Ωcm , and 24.1 cm2/Vs, respectively.

並列關鍵字

plasma ； metal-organic chemical vapor deposition ； p-type ZnO ； gallium arsine ； rapid thermal process

參考文獻

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