微液噴墨技術具有大量生產、低成本、製程富彈性、材料使用率高及不需光罩等優點，噴墨技術於電子產業之應用上逐漸吸引矚目。因此，近年來，壓電噴印技術於軟性電子具有應用前景及價值。
本實驗利用壓電噴印技術於軟性基板polyimide上製備各式圖樣。所使用之金屬前驅物為硝酸銀水溶液，此溶液濃度為45 wt%，以及poly(N-vinyl-2-pyrrolidone)濃度為2 wt%；當壓電噴墨頭接收到雙脈衝訊號後，即可噴射形成單一顆液滴；液滴覆著於基板後，於常溫壓下進行乾燥；最後，還原出導電圖形於基材上方。為了獲得均勻成形之導線，基板需利用紫外線臭氧乾式清理成親水性表面性質。噴印之導線是否均勻成形，則受基板移動速度、液滴間距、基板溫度、燒結溫度及氣氛所影響。
觀察噴印結果發現，於基板溫度30及50oC，液滴間距20至50 µm下，可得到之線寬介於45至60 µm之間。最佳噴印品質可於噴印條件：基板溫度30oC、基板移動速度1 mm/ s及液滴間距30 µm，乾燥後圖形於乙二醇蒸氣經300oC處理20分鐘還原後，獲得均勻線寬100 µm之導線，最佳電阻率為3.4 x 10-5 Ω•cm。

The advantages of drop-on-demand ink jet printing include mass production, low cost, flexibility, high ink utility rate and without using mask. Therefore, ink jet printing is one of the most promising techniques to fabricate conductive patterns in flexible electronic industry.
Continuous and uniform micro-conductive lines, printed on flexible polyimide substrate, without formation of bulges produced by the operation of drop-on-demand piezoelectric ink jet printing technique were investigated in this study. Silver nitrate water-based solution of 45 wt% concentration, which also contains 2 wt% of poly(N-vinyl-2-pyrrolidone), were employed as a metal precursor for metallization. Drops were formed by using bipolar pulse. The printed patterns were dried under room temperature and normal pressure condition. In order to obtain a hydrophilic surface, an ultraviolet (UV)/ozone (O3) treatment was carried out to clean polyimide substrate. Influence of operating parameters on uniform tracks formation includes substrate moving velocity, substrate temperature, dot-spacing, curing temperature and curing atmosphere. The uniform dots and continuous lines were produced at substrate temperature of 30 and 50oC in dotspacings from 20 to 50 µm; the diameter of dots was about 60 µm and the width of lines ranged from 45-60 µm.
The experimental results show that the resistivity of conductive tracks under substrate moving velocity with1 mm/s, substrate temperature of 30oC and dotspacing of 30µm is 3.4 x 10-5 Ω•cm with line width of 100 µm, which is one order higher than bulk silver. This value of resistivity was achieved by using ethylene glycol vapor reduction method at curing temperature of 300oC for 20 minute.

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