柔性電極為可穿戴式裝置之重要組件，其係由金屬導線印製於超彈性基板上並連接各式感測器所構成。柔性電極之設計除了超彈性基板外，基板上之金屬導線路徑設計亦為一大關鍵，與可穿戴式裝置之可撓性及可拉伸性息息相關。
本論文旨在探討一柔性電極中，不同材料金屬導線在不同幾何設計下之拉伸力學行為以及破壞機制。現今之柔性電極大多由超彈性基板/銅線構成，因銅線可印製上之超彈性基板總類較少，且製程較繁複，致侷限其發展。本論文擬探討之超彈性基板/銀/銅及超彈性基板/銀結構，則係先由網版印刷(Screen Printing)印製出銀種子層，再電鍍出銅導線，具有可大量生產、製程簡單等優勢，故本論文將以超彈性基板/銀/銅及超彈性基板/銀結構為基礎，探討影響金屬導線拉伸機械行為(應力、可拉伸度)之重要幾何與材料因子。
首先，本論文選擇一擁有高扭曲和高拉伸等特性之超彈性材料熱塑性聚氨酯(Thermoplastic Urethane, TPU)作為基板之材料，並於基板上印製金屬導線銀/銅與銀。對可拉伸熱塑性聚氨酯基板、銀及銅試片分以微拉力測試儀、壓痕量測試驗儀，進行材料機械性質之量測。因網版印刷之銀電阻率較高，本論文將同時分析熱塑性聚氨酯基板/銀試片拉伸後之電阻變化，以兼顧熱塑性聚氨酯基板/銀之拉伸性與電性表現。
接著建立熱塑性聚氨酯基板/銀/銅及熱塑性聚氨酯基板/銀電子電路元件之有限元素分析模型，探討不同幾何及材料因子下之金屬導線線路的非線性拉伸機械行為及破壞機制，並比較熱塑性聚氨酯基板/銀/銅及熱塑性聚氨酯基板/銀電子電路元件之優缺點。
最後，在同時考慮電性表現及可拉伸性下，經參數化分析及田口氏實驗設計後，本論文設計出一方形導線路徑，在週期數為12、線寬為0.1mm及狹縫寬比值為0.5時，於15%拉伸量下，最大塑性應變僅有1.7%，電阻變化率遠小於10%且電阻為6.7歐姆。本論文之成果可供設計導線路徑之參考，使柔性電極擁有可高拉伸及高機械/電性可靠度。

Stretchable electronic circuit is an important component of a wearable device. It consists of hyperelastic substrates and metal interconnects connecting sensors. In addition to the hyperelastic substrate, the design of metal interconnects paths on the substrate is also a key issue, which is closely related to the flexibility and stretchability of wearable devices.
The purpose of this paper is to investigate the tensile mechanical behavior and failure mechanism of metal interconnects of different materials in stretchable electronic circuits. Most of today's stretchable electronic circuits are composed of hyperelastic substrates/copper interconnects. Because of the small number of hyperelastic substrates that copper interconnects can be printed on, and the complicated process, the development is limited. In this paper, the hyperelastic substrate/silver/copper and hyperelastic substrate/silver structure are discussed. Because the silver seed layer is printed by Screen Printing, and the copper interconnect is electroplated, with the advantages of mass production, simple process, etc, this paper will use the hyperelastic substrate / silver / copper and hyperelastic substrate / silver structure to explore the important geometric and material factors affecting the tensile mechanical behavior (stress, stretchability) of metal interconnects.
First of all, Thermoplastic Urethane (TPU) was selected as the material of a substrate, and silver/copper and silver interconnects were printed on the substrate. The mechanical properties of the Thermoplastic Urethane, silver and copper were measured. Due to the high resistivity of screen printing silver, electrical performance and stretchability will be considered.
At last, after parametric analysis and taguchi experiment design, this paper designed a square metal interconnects path. When the cycle is 12, the line width is 0.1mm, and a slit width ratio of 0.5, the maximum plastic strain is only 1.7% at 15% stretching, the resistivity is far less than 10% and the resistance is 6.7 ohm. The results of this paper can be used as a reference for the design of metal interconnects paths to have high mechanical and electrical reliability.

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