氧化鎳是具有潛力的p型透明導電膜材料，但是由於氧化鎳的光電性質仍無法於產業中實際應用，故想藉摻雜鋰原子於氧化鎳薄膜之中，及改變薄膜沉積的基板溫度，以改善薄膜透光率、導電性質及穩定性。
本研究以射頻磁控濺鍍，利用氧化鎳陶瓷靶或是碳酸鋰片結合氧化鎳靶之複合靶材，進行薄膜濺鍍沉積，再藉由改變濺鍍時的基板溫度，以得到不同性質之氧化鎳薄膜。接著利用電子微探儀與感應電漿耦合質譜分析儀做成份定量；以二次離子質譜儀進行薄膜縱深成份分析；使用低掠角X光繞射分析及掃瞄式電子顯微鏡進行薄膜結構與結晶性分析；以X光光電子能譜分析薄膜中化學鍵結情況。導電性方面，則利用四點探針、霍爾量測及電性時效裝置得到薄膜電阻率變化，及其中載子濃度與載子遷移率等資訊，並對電穩定性做長時間觀察。而在光學性質方面，則是以紫外光-可見光光譜儀量測不同波長時的薄膜穿透率。
研究結果分析顯示，摻雜鋰於氧化鎳薄膜中最大含量為7.4at%，並且製程中所有薄膜氧原子/金屬原子比值皆大於一。經由XRD結構分析，推論氧原子佔據格隙位置為薄膜氧原子/金屬原子比值大於一的主要因素。濺鍍時升高基板溫度，會使薄膜中的氧原子逐漸脫離，但也會增加鋰離子摻雜量。在導電性質方面，最佳電阻率是在鋰摻雜量為7.4at%，基板溫度200℃時所得之8.4×10-2Ω-cm，而鋰摻雜確實造成載子增加，進而降低電阻率。而電穩定性方面，摻雜鋰與提升基板溫度都有助於減緩電性時效問題，推測是鋰離子與易與水氣中的氫氧根結合，減少了氫氧根與電洞結合的機會。至於光學性質方面，穿透率約在30%~50%，經過計算後的能隙也較氧化鎳塊材為小。由此可知，摻雜鋰雖能改善導電率及電性時效問題，相對的會減低薄膜光學穿透率。

Nickel oxide is regarded as a potential material of p-type transparent conducting oxide. Unfortunately, the optical and electrical performances of nickel films can’t be still applied to industry. Therefore, we try to improve the transparency, conductivity, and electrical stability by doping lithium atoms in nickel oxide thin films and changing the substrate temperature.
In this study, nickel oxide thin films were prepared by NiO target and NiO+Li2CO3 composite target. By changing substrate temperature during thin films deposition, they would exhibit different properties. Then, nickel oxide film compositions were determined by FE-EPMA and ICP-MS. Elemental depth profiles were explored by SIMS analysis. As for structure and crystallinity of nickel oxide films, we used GIAXRD and SEM to characterize them. The chemical bondings of nickel oxide films were investigated by XPS. Four-point probe, Hall measurement and electrical aging equipment were used to obtain resistivity, carrier density, mobility and electrical stability. We also used UV-Vis spectrophotometer to measure the transparency of nickel oxide films accompanied various wavelength.
The experimental results show the content of lithium could reach 7.4at% in nickel oxide thin films, in which the ratio of O/(Ni+Li) are always greater than 1. According to XRD results, it’s suggested interstitial oxygen atoms are dominant factors. Rising substrate temperature would not only make oxygen atoms evaporate from the nickel oxide films, but also increase the amount of dopants. About the electrical performance, the lowest resistivity we have obtained is 8.4×10-2Ω-cm when the content of lithium is 7.4at% and substrate is heating at 200℃ due to the increasing of carrier density by doping lithium in the nickel oxide. It is found electrical aging properties slow down because of increasing lithium content and rising substrate temperature. It’s suggested lithium ions may react with hydroxyl of hydrosphere, and then lower the combinative probability of hydroxyl and electric holes. As for optical properties, the transparency of nickel oxide films is from 30% to 50%. And calculated energy gap is smaller than bulk NiO. In conclusion, conductivity and electrical aging properties are improved by doping, but properties of transparency are decreasing in opposite.

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