微滴喷射化学沉积工艺条件对成形银导线的影响

Influence of process conditions on silver conductive lines by micro-droplet jet printing solution reaction

为制备具有良好导电特性的柔性线路,研究了织物表面微滴喷射打印化学沉积的工艺条件变化对成形导电线路性能的影响。利用开发的气动式双喷头微滴按需喷射系统,通过改变反应溶液中硝酸银和抗坏血酸的用量、分散剂聚乙烯吡络烷酮(PVP)的浓度及反应体系的pH值,在系统稳定喷射条件下打印导电线路,对不同条件下成形导线的微观形貌进行观察,并测试成形导线的方阻。结果表明:在稳定喷射条件下,当硝酸银和抗坏血酸用量分别为50%和30%(质量体积比)时,反应生成的银导线平均方阻为2.92Ω/,标准差为0.46Ω/;分散剂PVP在银导线反应过程中具有控制银微粒大小和改善粒子间团聚的作用,且当分散剂PVP添加量为6%时,银颗粒成"米粒"状,颗粒间连接成网状结构;不同pH值条件下反应体系的反应情况不同,当反应体系的pH值为2～3时,反应生成银粒子较多,且颗粒形状规则统一。

In order to prepare flexible circuit with good electrical conductivity, the influence of the process conditions of droplet jet printing forming the chemical deposition on the performance of the formed conductive circuit was investigated. The double nozzle pneumatic micro-droplet injection system was applied by changing the concentration of two kinds of reaction solution, the concentration of PVP and the pH of the solution. Under the stable system to proceed wire jet printing, the microstructure produced under different conditions were observed and the square resistance were measured. The results shows that when the silver nitrate concentration and the ascorbic acid concentration are 50% and 30%, respectively, the average square resistance of the silver wire is 2.92 Ω/□, and the standard deviation is 0.46 Ω/□, PVP has the effect of controlling the size of silver particles and improving the agglomeration between particles during the reaction of silver conductive lines. When PVP content is 6%, the scanning electron microscopy images show that the silver particles are rice-like, and the connection between particles present a network structure. The reaction conditions vary with pH value, and when the pH value is 2 to 3, more silver particles are prepared and the grain shape is uniform.