透明導電的p-type氧化鎳(NiO)薄膜有可能是p-type GaN的極佳歐姆接觸材料。在作為GaN歐姆接觸材料的應用上，我們希望得到具有高可見光穿透率及高導電率的氧化鎳薄膜。
本研究利用射頻反應性磁控濺鍍（RF reactive magnetron sputtering）系統，以不同的製程條件在康寧玻璃1737F基板上沈積氧化鎳薄膜，以探討濺鍍方法成長氧化鎳薄膜時各濺鍍參數如：射頻功率、基板溫度、濺鍍壓力與氧氣流量比，以及濺鍍完畢後熱處理條件對所沈積氧化鎳薄膜微結構及性質之影響。實驗分析上採用a-step量測膜厚，四點探針量測電性，可見光光譜儀量測透光率，X光繞射儀分析薄膜之結晶結構，SEM分析進行表面與截面型態觀察。
實驗結果顯示氧化鎳薄膜之電性與光性跟氧氣流量比及基板溫度有密切關連性。另外，過量的氧原子所引起的導電機構推測是氧的間隙原子。熱處理使得氧化鎳薄膜中不穩定之過量氧原子脫離薄膜，使得薄膜電阻率隨熱處理溫度之上升大幅提高，而因熱處理使氧化鎳薄膜之結晶結構較完美，使得可見光穿透率增加。

Nickel oxide films may be good ohmic contact material for p-type GaN. As for the ohmic contact electrode of GaN, nickel oxide films need to be prepared for better materials in high transmittance and conductivity.
By RF magnetron reactive sputtering, NiO thin films were deposited on Coring 1737F glass with various sputtering parameter in this study. The aim of this study is to find out how the depositing parameters, like RF power, substrate temperature, sputtering pressure, and oxygen flow ratio as well as annealing affect the microstructure and properties of the film. Film thickness was measured by an a-step profilometer. The resistivity was measured by a four probe method. The transmittance was measured by visible light spectrophotometer. The XRD patterns were used to analyze the crystal structure of the films, and SEM observations indicate the surface and cross section morphology of NiO films.
The results reveal that oxygen flow ratio and substrate temperature have strong influences on the electrical and optical properties of NiO films. We suppose that conductive mechanism affected by the interstitial oxygen atoms by lattice constant from XRD patterns. Heat treatment make unstable excess oxygen atoms break away from NiO structure.The effects result in that the resistivity and transmittance of NiO films increase with annealing temperature rise.

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