本論文探討利用伽凡尼置換反應製備銀銅顆粒之動力學研究，藉由奈米銀做為金屬銅粉接觸的黏著劑，以降低銅金屬接觸電阻。在低溫200℃燒結，可在金屬銅氧化前熔融奈米銀，以防止銅之氧化，另一方面導電率即可大幅增加。對於提升銅膏的導電率以及降低燒結溫度會有極大的幫助。
利用置換反應製備奈米銀粉包覆銅粒子，觀察製備之銀－銅粉末隨時間、溫度及多種因素對粒徑大小之影響，進而分析置換反應對銀－銅粉末之動力學現象。藉著改變硝酸銀含量、添加之分散劑含量、置換反應時間、置換反應溫度，觀察對銀顆粒結構的影響。結果發現，硝酸銀與銅粉莫耳數比為1：0.5時，銀顆粒還原速率獲得控制，形成分支明顯且完整的結構；本實驗使用兩種溶劑，包括去離子水以及乙二醇，由於有機溶劑乙二醇之極性致使置換反應速度趨於平緩，另添加0.5 wt.%之分散劑 （聚乙烯吡咯烷酮），有較好的分散較果，在此分散效果下，銅粒子被奈米銀完整包覆；反應最佳時間30分鐘，銀顆粒有足夠反應時間被還原出來，並且形成分支明顯的奈米銀結構；而在溫度控制方面，低溫致使反應過慢，無法完整生長出包覆完全之奈米銀粒子。另外由表面成分分析結果可知，銀-銅製換反應過後，表面之銀比例約為95%以上，形成完整的奈米銀結構包覆銅粒子。

This study is probing into the kinetic influence in silver-copper replacement reaction. In order to reduce the contact resistance, copper powder contact each other with the binder, silver nanoparticles. Silver nanoparticles will melt at 200℃ before copper powder is oxidized. This mechanism can not only prevent copper from oxidized, but enhance the conductivity.
Silver-copper powder is prepared by replacement reaction. Through changing the content of silver nitrate, the content of dispersant (PVP), reaction time and reaction temperature, the result shows replacement reaction has an impact on the grain size. Moreover, the kinetic study can be analyzed. The conclusion of this study represents when the molar ratio of silver nitrate to copper powder is 1:0.5, using ethylene glycol as solvent, adding 0.5 wt. % PVP, at room temperature, the reduction rate of silver particles could be controlled, and forming nanostructure silver which has obvious branch structure. The dendritic structure silver formed smaller and obvious branch structure. When reaction time is 30 minutes, there is enough time to produce silver nanoparticles, obvious dendritic structure. In the other side, if the temperature of reaction is too low, copper powder can’t be coated completely. A weight percent of silver is more than 95% on the surface by energy dispersive spectrometer analysis. This result shows silver nanostructure covered on copper in a good shape.

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