3D-IC以矽晶圓穿孔導通銅線路來進行晶圓與晶圓間垂直整合，藉此可以提供高效能、低耗電和微型化之電子元件，因此3D-IC銅對銅接點技術為下個世代重要關鍵技術。
本研究利用壓電噴墨原理探討奈米銀粒子漿料在3D-IC對接之銅墊片常見的擴展行為(overflow)，本研究中利用三脈衝波型調整奈米銀粒子漿料的微液滴體積大小，並探討不同噴印間距、微液滴體積大小、機台偏移量與基板性質與噴墨品質間的關係。所有轉移行為包括微液滴飛行
、碰撞及微液滴延展皆利用高速攝影機觀察，高速攝影機無法觀察部分則利用商用流體力學計算軟體Flow-3D®輔助觀察。
由結果可知噴墨模式下的漿料轉移比點膠模式下的漿料轉移更不容易有擴展行為(overflow)行為；而在200 μm噴印間距下，機台偏離基板中心25 μm不會造成擴展，但機台偏離基板中心35 μm卻會造成擴展，而漿料轉移至有OSP銅墊片及無OSP銅墊片均不會造成微液滴擴展現象。

In this study, we have demonstrated that the highly concentrated nano silver particles ink was precisely transferred on the small Cu pads. In order to understand the overflowing phenomenon, the effect of the waveform condition and the other printing condition was investigated. For the higher pulse range of +40 V-−22 V, the droplet diameters of 42 μm with an average velocity of 0.21 m•s−1 was produced; For the lower pulse range of +30 V-−20 V, the droplet diameters of 24 μm with an average velocity of 1.3 m•s−1 was produced. The droplet would overflow if the gap between nozzle and the copper pad is lower than 200 μm.The droplet transferred on the copper pad with OSP and without OSP doesn’t occur overflow. The droplet would not overflow if the distance between droplet and the copper pad center is lower than 35 μm.

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