壓電噴墨技術是一種溶液式製造方法，利用微液滴沈積於基板上，堆疊出圖形或是精微結構之結果。此技術優點為非接觸式直接製造方法，不需要光罩或是任何相關微影技術步驟。噴印品質會受微液滴行為所影響控制，因為不同噴墨條件下，觀察到流體力學現象也會不一樣。
本研究採用水基系列墨水為研究主軸，目的在觀察分析微液滴形成過程，及建立壓電噴印技術之理論基礎。微液滴行為則是探討，微液滴形成過程中可能發生，液柱發展模式及斷裂方式、衛星液滴、主液滴及液滴碰撞合併等狀況。另一個研究目標，則是找尋單一顆微液滴行為之最佳噴印條件，並且藉由噴墨條件改變控制液滴大小及速度。此外，為了研發低溫製程步驟，製備導電圖形，採用三種金屬導電墨水材料，以利朝向軟性電子及微電子應用發展。
黏度較高之溶劑及添加溶質之導電墨水材料，皆需要把脈衝電壓增大方可噴射出微液滴，微液滴行為有三種：單一顆液滴、兩顆液滴碰撞合併及衛星液滴。利用無因次參數分析，可以對脈衝波形中驅動電壓大小及單一顆液滴行為之大小，進行製程條件調整提供預測參考。不同濃度之硝酸銀水溶液之圖形噴印結果，陣列圖形中點直徑為60-220 μm，線寬約為100-600 μm，而噴覆出薄膜經還原後，經XRD圖譜顯示純銀之繞射峰訊號，SEM可觀察到緻密的薄膜表面型態，其最佳電阻率為1.9 x 10-6 Ω•cm。

Piezoelectric ink-jet printing technology was a droplet deposition method used for liquid phase materials. Ejected micro-droplets were deposited only on the demand positions, resulting in the printing patterns and constructing micro-structures on the substrates. The benefit of ink-jet printing in a non-contacted mode exhibited simpler processing procedures without mask preparation or any lithography process. The printing quality was controlled by droplet behaviors due to various rheological phenomenons performed under different printing conditions.
The water-base ink materials were employed in this study for observing droplets evolution during ink-jetting and establishing the fundamental principles of the ink-jet printing method. Droplet behavior for ink materials elucidates quantitatively the fluid mechanics of DOD droplet behavior including the time evolution of liquid thread shape, breakup of liquid thread, satellite formation, and combination of satellites and primary droplet. The other objective is to obtain controlled parameters, droplet diameter and velocity for the most stable single droplets formed. In order to fabricate conductive patterns, three kinds of conductive ink materials were conducted into the lower processing temperature for flexible electronics and microelectronics applications.
For the higher viscosity and additives of ink materials, the pulse voltages of waveform were increased to eject micro droplets from the nozzle. Three different modes of ejection were observed; single droplet, double droplets with subsequent recombination, and droplet with satellites. The appropriate dimensionless groups were employed in comparing and analyzing droplet formation process. Silver nitrate water-based solution of varied concentrations resulted in the dot diameter of matrix pattern between 60-220 μm and the line width from 100 μm to 600 μm. The XRD diffraction pattern of printed silver film after reduction at 200oC by ethylene glycol vapor for 10 min shows the peak characteristic of metallic silver. The optimum resistivity of the silver film is 1.9 x 10-6 Ω•cm measured by the four-probe method due to the dense and continuous surface morphology observed by SEM image.

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