銦錫氧化物(Indium tin oxide, ITO)具有著良好的透光度以及導電性，在透明電極發展中有著相當重要的地位，然而ITO相當缺乏機械性質，無法應用於發展中的撓性面板或穿戴式電子產品的電極。大量的研究指出透過金屬金、銀、銅製作的可撓電極有很大的機會可以取代ITO，然而金、銀昂貴，銅容易因為氧化失去電性，故本研究旨在開發一種可以降低成本且壽命較長的銅鎳合金電極，並以可在大氣環境下直接製作之雷射直寫技術製造，最後在高溫環境檢測不同銅鎳成份比合金電極之電性變化。
甲酸鎳和甲酸銅皆為可加熱自還原的有機金屬鹽類，最大的優點是無須還原劑。本研究透過混合不同莫耳數比的甲酸銅以及甲酸鎳於有機溶劑中，將製備完成的複合金屬墨水塗佈於玻璃基板形成均勻薄膜，透過50倍聚焦532 nm綠光雷射誘發甲酸銅以及甲酸鎳的熱分解並且燒結，搭配移動平台可以在無需光罩且在大氣環境下進行金屬的圖案化，透過上述方法可以製作出片電阻 70 Ω/□、透光度大於80%、平均厚度500 nm的透明銅鎳合金網格電極。
研究指出銅在高溫環境下會因為氧化而大幅度提升電阻，於本研究中，將純銅網格電極以及不同比例的銅鎳網格電極放置於250 °C加熱器上，銅網格電極在1~2小時電阻值變化約為106 倍，而銅鎳網格電極(溶液中Cu:Ni=1:2)經過48小時電阻值變化不超過3倍。

Indium tin oxide, ITO, has good performance in both transmittance and conductivity. Thus, it has been playing an important role in transparent conducting electrodes. However, ITO is brittle that restricts its applications in the blooming flexible electrotrincs. Many research reports reveal that metal-mesh-based electrodes by varios metal materials such as gold, silver, and copper, have demonstrated high potential as alternative transparent electrodes. However, gold and silver are too expensive and copper is easy to get oxidated either at the duration of fabricating process or in the course of operations. Thus, this study is committing to develop a low-cost alloy electrode that is with high oxidation resistance. We aim to develop a copper-nickel-alloy-based metal mesh electrode fabricated by the technique of laser direct write. The resulting capability in oxidation resistance is tested in an elevated temperature environment.
Copper formate and nickel formate are all metal organic thermal decomposition (MOD) compounds that take the advantages in both reducing to metal ions without the need of any reducing agents and obtaining the resulting various compound solutions by mixing both inks at different molar ratios. The mixed MOD solution is then spin-coated on a glass substrate and dried in vacuum at 100 °C to form a uniform MOD thin film. It is then heated by a focused 532 nm laser beam to induce thermal decompositons of both copper formate and nickel formate and sintered reduced copper and nickel particles. The pattern of the resulting metal-mesh can be accomplished by laser direct wirte, a maskless process and executable in the ambient. Results show that the fabricated copper-nickel alloy electrode exhibit good characterisitics: sheet resistance less than 70 Ω/□, transmittance over 80% and the average thickness about 500 nm.
Copper is very easy to get oxided, expecially at high temperatures. The excellent ability in oxidation resistance of our copper-nickel mesh elelctrode is examined in an oven maintaining at temperature up to 250 °C for 48 hours. The resistance increasement is only 3 folds, which is much more smaller than that of a copper mesh electrode that shows 106 times in resistance enhancement.

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