在電子產品追求輕、薄及可撓曲的趨勢下，軟性電子技術近年來發展非常快速。然而，頻繁的彎折常會造成軟性電子產品上的銀線線路之斷裂破壞而導致產品失效。因此，銀線線路之機械性質及力學行為探討，對軟性電子產品可靠度之提昇，極為重要。
由於銀線線路材料性質的量測受限於其尺寸較小，而不易利用拉伸實驗獲得，雖可藉奈米壓痕實驗測得其硬度及楊氏模數，但對銀線線路之彈-塑性性質仍無法準確獲得。Dao等人(2001)曾提出一材料分析模型，雖可探討楊氏模數範圍在10~210GPa、降伏應力範圍在30~3000MPa以及應變硬化指數範圍在0~0.5間之材料的彈-塑性性質，但因其分析模型為對數形式，易求出不合理的負數材料性質，致使分析模型之應用性受到侷限。為解決上述缺失，胡(2015)針對Dao等人(2001)之材料分析模型進行修正，惜並不涵蓋銀線材料之材料性質範圍。
本論文主要以胡(2015)之修正型Dao材料分析模型為基礎，建立一適用於銀線線路材料性質範圍之分析流程，並結合奈米壓痕實驗之結果及有限單元模擬，以預測銀線材料於不同外加溶劑比例之彈-塑性材料性質。此外，本論文並利用場發射掃描式電子顯微鏡及穿透式電子顯微鏡觀察銀線材料的表面結構以及其內部元素的組成分布，探究造成銀線材料於不同外加溶劑比例下之彈-塑性材料性質變化的原因。最後，本論文亦探討銀線材料在不同環境溫度下之彈-塑性材料性質。
本論文研究成果將有助於可撓式軟性電子彎曲疲勞壽命之分析，提昇軟性電子產品之可靠度。

Under the pursuit of the trend of light, thin, and flexible electronic products, the flexible electronic technology develops fast in recent years. However, the breakage of the silver line on the flexible electronic products are formed because of frequent bends, and it often leads to the failure of the products. Therefore, the discuss for the mechanical properties and behaviors of the silver line is extremely important for raising the reliability of flexible electronic products.
Owing to the measurement of the material properties for silver line is limited by its small size, it is not easy to obtain it by tensile tests. Although the hardness and Young’s modulus can be measured by nanoindentation tests, the elastoplastic properties of silver line are still not obtained accurately. Dao et al. (2001) proposed a material analysis model. Although it can explore the elastoplastic properties for materials in the range of 10~210 GPa for Young’s modulus, 30~3000 MPa for yield stress and 0~0.5 for strain hardening exponent, the relationships in the analysis model are logarithmic form which are easy to solve unreasonable or negative material properties and result in the limitation of the application for the analysis model. In order to solve the problems, Hu (2015) revised Dao et al.’s material analysis model, but it doesn’t cover the material properties of silver line.
Based on the modified Dao material analysis model of Hu (2015), an analytical process which is suitable for the range of the material properties of the silver line is constructed in this study and it combines the results of nanoindentation tests and finite element simulation to predict elastoplastic material properties of the silver line with different proportions of solvent added. In addition, the surface structures and the distribution of the inner elements of the silver line are observed by field emission scanning electron microscopy and transmission electron microscopy to find out the reasons which cause the changes of the elastoplastic material properties of the silver line with different proportions of solvent added. Finally, the elastoplastic material properties of the silver line at different temperatures are also discussed in this study.
The achievement of this research is helpful for the analysis of the bending fatigue life of flexible electronics, and enhances the reliability of flexible electronic products.

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