利用田口方法優化銀包銅粉化學鍍製程參數之研究

Optimization of chemical plating process for silver-coated copper particles by Taguchi method

周聖浩(Sheng-Hao Chou)

指導教授 ： 余炳盛 ； 王玉瑞

國立臺北科技大學/工程學院/資源工程研究所/碩士(2014年)

摘要

銀粉為導電膠重要的原料，常占總成分約80%，廣泛應用於太陽能電池、觸控面板、PCB填孔、LED…等等。產品之銀粉使用量及成本攸關產業競爭力，故為了降低成本，將粉末以銅粉為主體，並於其表面鍍銀，製備銀銅殼核粉末，可減少銀的使用量，成本亦降低，為未來主要發展趨勢。
本研究以化學鍍法(Chemical Plating)製備銀銅殼核粉末，並依據田口方法(Taguchi methods) L18(21×37)直交表規劃，化學鍍法是將適量螯合劑溶液加入硝酸銀溶液中，並添加還原劑使銀還原，均勻沉積在銅粉表面上。量測粉末之電阻值後，經由田口分析找出最佳實驗參數為反應溫度：15℃、銅銀計量比：2、硝酸銀濃度：0.464 M、氨水與硝酸銀莫耳比：4、還原劑與硝酸銀莫耳比：1.5、攪拌速率：800 rpm、溶液添加速率：20 ml/min、反應時間：20 min。所製得的銀包銅粉進行酸溶，再利用ICP分析溶液中銅銀濃度，計算粉末之銅銀重量比。SEM 、XRD檢驗顆粒表面形貌及相純度。銀包銅粉在150℃高溫爐中進行熱處理24小時後，測量電阻值之變化。最佳化實驗結果測得銀包銅粉末平均電阻值約14.8 mΩ，電阻率2.35 mΩ•cm。

關鍵字

田口方法 ； 化學鍍 ； 銀包銅粉

並列摘要

Silver powder is an important raw material for conductive paste, often greater than about 80% of the total composition, widely used in solar cells, touch panels, PCB hole filling, LED ... etc. Silver usage amount and cost of products relevant to industrial competitiveness, Therefore, in order to reduce costs, the copper powder as the main body, and silver coated on its surface. Preparation of silver-copper core-shell powder can reduce the amount of silver, this is a development trends in the future.
In this study, silver-copper core-shell powder was prepared by chemical plating, and based on the Taguchi method L18 (21 × 37) orthogonal array. Chemical plating is used solution of the chelating agent added to the amount of silver nitrate solution, and adding a reducing agent to deoxygenate silver, let it uniformly deposited on the copper surface. After measuring the resistance value of the powders, analyzing by Taguchi to find the optimal experimental parameters. For optimal experimental parameters, reaction temperature：15℃、copper-silver ratio：2、concentration of silver nitrate：0.464 M、molar ratio of ammonia and silver nitrate：4、molar ratio of reductant and silver nitrate：1.5、stirring rate：800 rpm、addition rate of the solution：20 ml/min、reaction time：20 min. The concentration of copper and silver in core–shell particles which we obtained were investigated by ICP analysis through acid-soluble, calculate the weight ratio of copper and silver for powders. Morphology and phase purity of the particles were investigated by scanning electron microscopy(SEM) and X-ray diffraction (XRD). After heat treatment at 150℃ for 24hr, Silver-coated copper particles were measured the change of resistance value. The optimal experimental results, the resistance of powders was about 14.8 mΩ, resistivity was about 2.35 mΩ•cm.

並列關鍵字

Taguchi methods ； Chemical Plating ； silver-coated copper particles

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