Palladium-Free Surface Metallization of Polycarbonate Substrate by a Chemical Grafting Technology

近年來隨著科技的進步、無線通訊技術的普及化及雲端科技的廣泛應用，使得無線電子通訊應用產品不得不朝向輕、薄且功能多元化的趨勢發展。在薄型化及功能多元化的市場需求下，電子通訊應用產品面臨了高佈線密度及高傳輸速率的問題，為因應高傳輸通訊速率，天線導體的設計及製作已成為無線通訊技術發展的重要基礎。現今天線製作方法是預先將金屬觸媒混埋於高分子材料中，經由雷射雕刻程序裸露及活化基材表層的金屬觸媒後，完成金屬天線之製作，但此方法易產生觸媒裸露不均或含量不足等問題，而導致後續無電電鍍銅出現漏鍍或不起鍍的瑕疵。為改善此一製程，曾有文獻提出化學蝕刻及電漿表面處理的方法，但其高汙染及設備昂貴的特性，使得低成本且低汙染的化學接枝技術逐漸受到重視。 本論文提出全濕製程且具綠色環保之表面金屬化方法，結合上快速化學接枝技術即可完成選擇性金屬化，並選擇以鎳、銅、銀觸媒來取代昂貴之鈀觸媒以催化後續無電電鍍銅，最後電鍍一層鎳以增加抗腐蝕及耐磨損性。本論文利用X光光電子能譜儀與衰減式全反射傅立葉紅外光譜儀檢視各步驟之化學鍵結狀態與其結構，並推測其反應機制，再以場發射掃描式電子顯微鏡及原子力顯微鏡觀察各實驗步驟之型貌變化及化學銅、電鍍鎳的緻密程度，最後利用膠帶測試來檢視銅層與基材的附著力。 實驗結果顯示溶劑之介電常數及濃度影響後續奈米鎳觸媒的催化活性，而當以醇類為接枝溶劑時，銅層具有良好附著力與均勻性，如此一來可免去雷雕方式並完成無鈀製程，大幅降低設備與製程上的成本。In recent years, the wireless communication and the applications of cloud technique become more popular. Since the rapid increase in technology, the development of wireless electronic products tend toward light, thin and multi-functional . It has some problems with high wiring density and transmission speed in electronic communication applications. Therefore, the design and fabrication processes of antennas in smart phones have become important for developing wireless communication technology. Currently, laser direct structuring (LDS) technology is the main process for fabricating the antenna of a smart phone. The first step is to mix metal catalysts into a polycarbonate(PC) substrate. The laser ablation can do surface patterning directly. The buried catalysts were thus exposed after laser ablation and could initiate the electroless copper deposition. However, if the exposed catalysts are not uniform or insufficient, the subsequent electroless copper plating will get some problems. To overcome the problems, a variety of surface treatment techniques for metallizing polymer materials have been extensively reported, such as chemical etching treatments, plasma modification…etc. However, they will cause the environmental pollution and they have some equipment limitations. So low-cost and low-pollution chemical grafting technology attracts much attention. In this study, we reported an environmentally friendly and a wet process for the surface metallization of PC. With chemical grafting technology we were able to achieve region-selective metallization. We used Ni, Cu and Ag metals as catalysts to replace Pd for initiating the copper electroless deposition. Finally, the nickel electroplating deposition was used to increase corrosion resistance of antenna. We use X-ray Photoelectron Spectrometer(XPS) and Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy(ATR-FTIR) analysis to observe the changes of chemical bonding and surface functional groups in each steps and speculate a reasonable reaction mechanism. Field Emission-Scanning Electron Microscope(FE-SEM) and Atomic Force Microscopy(AFM) analysis is used to observe the surface morphologies of copper and nickel films. Finally the adhesion between the deposited copper layer and the PC substrate was evaluated by Scotch tape test according to the standard peeling test. The results show that the concentrations and the dielectric constants of the solvents that are used for grafting reaction influence the subsequent catalytic activity of the nickel nano-catalyst. When we use alcohol as the solvent, the plated copper layer has good adhesion and uniformity on the PC substrate. This approach significantly reduce the cost of equipment and processes and accomplishes a Pd-free metallization process.摘要 i Abstract ii 目錄 iv 表目錄 ix 圖目錄 x 第1章 緒論 1 第2章 文獻回顧與理論 2 2.1 塑膠基材簡介 2 2.1.1 聚碳酸酯基材 2 2.1.2 聚對苯二甲酸乙二酯基材 3 2.1.3 聚醯胺基材 3 2.2 PC基材表面金屬化 6 2.2.1 蝕刻表面金屬化 6 2.2.2 表面改質金屬化 10 2.2.2.1 表面接枝技術 10 2.2.2.2 UV改質 11 2.2.2.3 雷射改質 11 2.2.2.4 電漿改質 12 2.2.3 溶膠凝膠法 14 2.2.4 表面濺鍍金屬化 15 2.2.5 雷射雕刻表面金屬化 16 2.3 噴墨印刷 17 2.4 無電電鍍 20 2.4.1 無電電鍍 20 2.4.2 鍍液組成與特性 21 2.4.3 中性無電電鍍銅的化學反應式與反應機制 24 2.5 附著力測試 28 第3章 研究動機與目的 29 第4章 實驗藥品、裝置與步驟 30 4.1 實驗藥品 30 4.2 實驗裝置 32 4.2.1 場發射掃描式電子顯微鏡(Field Emission-Scanning Electron Microscope，FE-SEM) 32 4.2.2 衰減式全反射傅立葉紅外光譜儀(Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy，ATR-FTIR) 34 4.2.3 X光光電子能譜儀（X-ray Photoelectron Spectrometer, XPS） 35 4.2.4 原子力顯微鏡(Atomic Force Microscopy, AFM) 36 4.2.5 接觸角量測儀(Contact Angle Measuring Instrument, CA) 38 4.3 實驗步驟 42 4.3.1 聚碳酸酯表面金屬化 42 4.3.1.1 PEI接枝以噴塗方式 42 4.3.1.2 PEI 接枝以浸泡方式 44 4.3.2 化學反應流程 46 4.3.3 聚碳酸酯無電電鍍銅、電鍍銅與電鍍鎳外觀 49 第5章 實驗結果與討論 50 5.1 聚碳酸酯表面金屬化探討 50 5.1.1 XPS能譜分析 50 5.1.2 ATR-FTIR能譜分析 63 5.2 前處理對聚碳酸酯表面之影響 64 5.2.1 鹼處理對聚碳酸酯表面之影響 64 5.2.2 紫外光改質對聚碳酸酯表面之影響 70 5.3 接枝劑對聚碳酸酯表面金屬化之影響 75 5.3.1 PEI溶劑效應 76 5.3.1.1 XPS能譜分析 78 5.3.1.2 AFM表面型態分析 81 5.3.1.3 表面CA量測結果 83 5.3.2 PEI濃度效應 84 5.3.2.1 XPS能譜分析 84 5.3.3 PEI接枝時間之影響 87 5.3.3.1 AFM表面型態分析 87 5.3.3.2 ATR-FTIR能譜分析 90 5.3.3.3 表面CA量測結果 93 5.3.4 溫度對接枝之影響 94 5.3.4.1 XPS能譜分析 95 5.3.4.2 AFM與SEM表面型態分析 96 5.3.4.3 表面CA量測結果 99 5.3.5 噴墨塗佈方式接枝 100 5.4 觸媒離子吸附 101 5.5 聚對苯二甲酸乙二酯基材表面金屬化 106 5.6 聚醯胺基材表面金屬化 109 第6章 結論 110 第7章 未來發展方向 112 第8章 參考文獻 11