奈米銀線網格薄膜具備低電阻、高透光度以及製程成本低等特性，是取代傳統應變計的候選材料之一，而製作柔性銀線薄膜電極是下一世代柔性及可伸展式電子元件的關鍵組件。本研究將奈米銀線鑲嵌至柔性聚氨酯(Polyurethane, PU)基材，製備電阻式應變感測器，並分析其特性。另一方面，該元件在溫度變化時，電阻也隨之改變，因此我們也探討該元件的感溫特性，使元件成為多功能感測器。
首先二階段多元醇結合溶熱法合成尺寸均勻、可控的奈米銀線，其長度60~80 µm、直徑100~120 nm，之後利用旋轉塗佈將奈米銀線均勻塗佈於玻璃基板表面，實驗上以改變旋塗次數變化奈米銀線堆積密度，也改善奈米銀線彼此連接性。結果顯示：塗佈1、3、5層的奈米銀線薄膜，其透光率分別為85.9%、80%、76.2 %。1層的奈米銀線薄膜可量測的最低應變達0.3%，在此應變下△R/R0=0.09、gauge factor(GF)=30，在1%的應變下 △R/R0=0.64、GF=64。但也發現1層奈米銀線薄膜因堆積密度低，導致拉伸時電阻變化不穩定，接著我們提高奈米銀線堆積密度(3層及5層)來提升在拉伸過程的穩定性，並擴大拉伸應變範圍至20%。
為了改善奈米銀線接點電阻過高及拉伸不穩定性的問題，我們利用熱處理(220 ℃、20 分鐘)及奈米銀線/PU表面鍍銅，熱處理後的奈米銀線，電阻值由原本約200降低至30.6 Ω，在1%的應變下 △R/R0=0.21、GF=21; 表面鍍銅的薄膜，電阻值降低至34.4 Ω，在1%的應變下 △R/R0=0.5、GF=50，兩者藉由奈米銀線接點電阻降低，使奈米銀線在拉伸過程電阻震盪幅度更為穩定，成功克服低密度奈米銀線的不穩定性。最後我們將奈米銀線/PU元件應用於溫度感測，隨著溫度的改變(27~59 ℃)，電阻值能有效快速響應溫度變化。
簡言之，在低密度奈米銀線薄膜,可偵測較低應變，且GF值高於其他文獻報導(應變0.5%，GF值僅20)，利用層數堆疊、熱處理以及電鍍銅於表面，因接點連接性佳，在拉伸過程不易斷開，雖會降低元件靈敏度，但能有效改善高應變下拉伸時的電阻穩定性，且該應變計元件的電阻能有效響應於溫度變化可應用為多功能感測器，以及應用於人體運動監測，顯示本研究可應用於未來伸展式元件。

Silver nanowire films have the characteristics of low resistance, high transmittance and low process cost, and nanowires embedded elastomers are considered as a potential candidate for replacing traditional strain gauges. In this study, silver nanowires were embedded in a flexible polyurethane (PU) matrix in order to prepare piezoresistive strain sensors. On the other hand, when the temperature changes, the resistance also changes, so we also explore the temperature sensing characteristics of the composite films.
First, two-stage process combining the polyol and the hydrothermal method was used to synthesize uniform and controllable silver nanowires with the length of 60-80 µm and the diameter of 100-120 nm. Then, the silver nanowires are uniformly coated on the glass substrate by spin coating, and the packing density of silver nanowires was controlled by changing the numbers of spin coating. The results show that the transmittance of the 1, 3, and 5 coating layers of silver nanowires is 85.9%, 80% and 76.2%, respectively. A 1-layer silver nanowires can measure the lowest strain to 0.3%. Under this strain, △R/R0=0.09, and gauge factor (GF)=30; while under 1% strain, △R/R0=0.64, and GF=64. However, it was also found that the 1-layer silver nanowire film was unstable due to its lower density. Then we increased the density of the silver nanowires (spin coating 3 and 5 layers) to improve the stability during stretching and expand the useful strain range to 20%.
In order to decrease both the high contact resistance and tensile instability of the silver nanowires/PU composites, we use heat treatment (220 ℃, 20 minutes) and copper plating to improve the joining of nanowires. The resistance of heat-treated silver nanowires is reduced from 200 to 30.6 Ω. When tested under 1% strain, the samples have △R/R0=0.21 and GF=21. While for the copper-plated films, the resistance is reduced to 34.4 Ω. When tested under 1% strain, the samples have △R/R0 =0.5, and GF=50. The improvement can be attributed to the reduced contact resistance of the silver nanowires, which makes it more stable during stretching. We successfully overcome the stretching instability of the low-density silver nanowire/PU samples. Finally, we apply the silver nanowires/PU elements to temperature sensing. As the temperature is changed (27~59 ℃), the resistance value can effectively and quickly respond to temperature changes.
In a nutshell, for samples with low-density silver nanowires, lower strain can be detected, and the GF value is higher than other literature reports (strain 0.5%, GF value is only 20). The reason can be the use of layer stacking, heat treatment and copper electroplating on the surface, which can help silver nanowires have better connection. It is not easy to break the connection during the stretching process, although it will reduce the sensitivity. It can effectively improve the resistance stability during stretching under higher strain, and the resistance of the strain gauge can also effectively respond to temperature changes. It can be applied as a multi-function sensor, including as sensors for human motion monitoring, and shows the potential of this device for practical application.

摘要
Abstract
致謝
目次
表目次
圖目次
第一章 緒論
1-1 前言
1-2 研究動機與目的
第二章 文獻回顧
2-1 透明導電薄膜的特性與應用
2-2 製備奈米銀線薄膜方法
2-2-1 邁耶棒塗佈
2-2-2 噴塗
2-2-3 滴鑄法
2-2-4 旋塗法
2-2-5 抽濾法
2-2-6 印刷
2-2-7 浸塗法
2-3 奈米銀線製備方式
2-4 銀奈米線接點焊接方法
2-4-1 光誘導等離子焊接
2-4-2 熱焊接
2-4-3 毛細力焊接
2-4-4 化學焊接
2-4-5 機械壓力
2-5 奈米銀線薄膜應用及奈米銀線應變計
第三章 實驗方法與步驟
3-1 實驗藥品
3-2 實驗架構
3-2-1 實驗總流程
3-2-2 奈米銀線/玻璃基板各種分析
3-2-3 奈米銀線/聚氨酯各種分析
3-3 RCA清潔玻璃基板
3-4 奈米銀線合成及塗佈
3-4-1 奈米銀線合成
3-4-2 奈米銀線清洗
3-4-3 旋轉塗佈奈米銀線
3-4-4 奈米銀線薄膜鑲嵌至聚氨酯
3-5 奈米銀線鑲嵌PU薄膜儀器分析
3-5-1 掃描式電子顯微鏡 (Scanning Electron Microscope,SEM)
3-5-2 可見光-紫外光分光光譜儀 (UV-Vis Spectophotometer)
3-4-3 四點探針(Four-point probe)
3-4-4 電子式萬用材料試驗機
3-4-5 精密恆電位儀
第四章 結果與討論
4-1 多元醇溶熱法合成奈米銀線探討
4-1-1 二階段結合法合成奈米銀線
4-1-2 添加溴離子合成奈米銀線
4-2 奈米銀線薄膜特性分析
4-2-1 不同奈米銀線含量轉印至PU前後之特性比較
4-2-2 不同奈米銀線含量鑲嵌於PU之特性
4-3 奈米銀線/PU拉伸電阻動態量測
4-3-1 不同奈米銀線含量之拉伸動態電阻量測
4-3-2 不同厚度之拉伸動態電阻量測
4-3-3 不同應變速率與響應時間關係
4-4低密度奈米銀線接點處理
4-4-1 熱處理
4-4-2 電鍍銅
4-5 奈米銀線薄膜應用
4-5-1 溫度感測
第五章 結論
參考文獻

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