反應性射頻濺鍍氧化鋅透明導電薄膜之成長機制及其特性之研究

Growth of Zinc Oxide Transparent Conductive Thin Films by Magnetron RF Reactive Sputtering and Studies of Their Properties

李岳修(Yueh-Shiu Lee)

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(2007年)

摘要

本論文利用反應性射頻磁控濺鍍法在載玻片、砷化鎵[111A]、[111B]、[100]基板上製備氧化鋅(ZnO)以及掺雜鋁的氧化鋅(ZnO:Al2O3)透明導電薄膜。探討 ZnO 導電薄膜之成長機制及其物理特性。
AZO(ZnO:Al2O3)薄膜的沉積製程條件中，是採取常溫下濺鍍、控制製程腔體壓力、氧氣的流量、以及薄膜沉積製程後 200℃ 退火持溫1、2和3 小時 ，進一步來探討 AZO 薄膜的電性、結晶性、結構、透光率特性，經由霍爾效應量測儀(Hall effect measurement)、 X光光學繞射儀(XRD)、電子顯微鏡(SEM)、紫外光(UV)光譜儀來分析其結果。本研究發現 AZO 薄膜具有(002)的優生方位，即朝 c-axis 成長的趨勢，氧氣佔總氣體比例越多時透光率會隨之增加，而在薄膜沉積製程後退火方面也可使電阻率降低、結晶性與透光率表現更佳，本實驗 AZO 薄膜沉積厚度 0.4 ?m 下得到最佳的電阻率~1.85 x 10-3 Ω-cm、載子濃度~2.99 x 1020/cm3、可見光光穿透率~90%。而在鍍 ZnO 薄膜的沉積製程條件是以基板加熱至 500℃、功率 100W、製程腔體壓力為 1 mTorr、控制氧氣流量來做結晶性和結構的物理特性，根據實驗結果發現到 ZnO 薄膜具有(002)的優生方位，即朝 c-axis 成長的趨勢，在不同的 GaAs 基板上有不同的沉積速率和結晶性。

並列摘要

In this study, zinc oxide (ZnO) and Aluminum-doped zinc(AZO) transparent conductive oxide (TCO) films deposited on GaAs[111A]、[111B]、[100] and glass substrate have been prepared by reactive rf magnetron sputtering. The growth mechanism and properties of the ZnO and AZO films were studied.
Aluminum-doped zinc(AZO) deposition was carried out at room temperature, various oxygen partial pressure, than annealed at 200℃ for 1、2 and 3 hours. The optical and electrical properties, surface morphology and microstructure of the sputtered Aluminum-doped zinc(AZO) thin films have been investigated by Hall effect measurement conductivity measurements, X-ray diffraction, SEM, spectroscopy(UV-VIS). The X-ray diffraction studies revealed AZO films have (002) preferred orientation with wurtzite structure. As oxygen concentration increase, the temperature of the films become higher. The annealed films have low resistivity, high temperature and quality crystallinity. The thickness of deposited AZO film were measured to be 0.4 um, to obtain lowest resistivity of ZnO in this study is 1.85 x 10-3 Ω-cm, carrier concentration is 2.99 x 1020/cm3 and reach high transparency of 90%. Zinc oxide (ZnO) deposition was carried out at 500℃, power 100 watt, various oxygen partial pressure. This result indicates ZnO films have (002) preferred orientation with wurtzite structure. The different GaAs substrate influenced crystal properties and deposition rate.

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