【作者】 王宁；

【导师】 梅乐夫；

【作者基本信息】 中国地质大学(北京) ， 材料科学与工程， 2020， 硕士

【摘要】 近年来,微纳加工技术与柔性可穿戴技术的发展对印刷电子行业提出了新的要求。其中,导电油墨是印刷电子材料中应用最为广泛的功能材料,是印刷电子产业开发的重点。目前,导电油墨的研究主要以导电性和导热性优异的银基油墨为对象,开发其在射频电子标签、可穿戴设备、太阳能电池、显示屏以及柔性传感器等电子器件中的应用。然而,传统的银纳米颗粒油墨所需后处理温度较高,限制了聚合物基材的使用范围,且打印过程中容易堵塞喷头。如何降低油墨打印的后处理温度,使其兼容各种聚合物基板是当前导电油墨及后处理工艺研发的重点,对柔性电子器件的发展起到至关重要的作用。无颗粒活性银油墨不受颗粒尺寸的限制,不含高分子的有机物,在较低的后处理温度下得到高导电性的银图案。本文以乙酸银为银前驱体,甲酸为还原剂,氨水作溶剂,制备了无颗粒的活性银油墨。采用喷墨打印技术在改性的聚酰亚胺基板上制备图案化银。分别通过热烧结和等离子烧结的方式将油墨中的银离子还原成银单质并实现纳米颗粒的互连。热烧结后,银导线的电阻率为1.2×10^-7Ω·m,是散装银电阻率的7.5倍;等离子烧结后,银导线的电阻率为8×10^-8Ω·m,是散装银电阻率的4.8倍。本文重点研究热烧结参数、等离子烧结参数和打印参数对银导线电学性能的影响规律,确定了优化的烧结参数;分析热烧结和等离子烧结还原并连接银纳米颗粒的机理。结果表明,通过改变热烧结、等离子烧结和打印参数可以很好的提高银导线的电学性能,改变其微观结构;提出了银纳米颗粒的烧结机理:热烧结和等离子烧结分别通过热传递和等离子活性物质来分解银油墨,使得银纳米颗粒还原并烧结;通过银导线化学成分分析比较了两种烧结工艺,等离子烧结效果优于热烧结;将两种烧结方式相结合,银导线的电阻率为6×10^-8Ω·m,仅为散装银电阻率的3.6倍。更多还原

【Abstract】 In recent years,the development of micro-nano processing technology and flexible wearable technology has put forward new requirements for the printed electronics industry.As the most widely used functional material in printed electronic materials,conductive ink has arisen great interest in the printed electronics industry.At present,as a kind of conductive ink,silver-based ink with excellent conductivity and thermal conductivity has been studied to develop for the application in electronic devices such as radiofrequency electronic tags,wearable devices,solar cells,displays,and flexible sensors.However,traditional silver nanoparticle inks are prone to clog the nozzle during printing,and the post-processing temperature required for the printed circuit is high,which limits the types of polymer substrates.Reducing the post-processing temperature of the conductive ink to make it compatible with various polymer substrates is the focus of current research,which will also greatly promote the development of flexible electronic devices.Since the particle-free activate silver ink is not limited by particle size,and does not contain organic matter,high conductivity silver patterns can be obtained at a low temperature.In this paper,particle-free active silver ink was synthesized with silver acetate,formic acid,and ammonia.And inkjet printing technology was used to fabricate patterned silver on the modified polyimide substrate.Thermal sintering and plasma sintering were used to reduce the silver ions in the particle-free activate silver ink and join the reduced silver nanoparticles.The resistivity of the silver wire sintered by thermal is 1.2×10^-7Ω·m,which is 7.5 times that of bulk silver.The resistivity of the silver wire sintered by plasma is 8×10^-8Ω·m,which is the resistivity of bulk silver 4.8times.In this paper,the influences of thermal sintering parameters,plasma sintering parameters and printing parameters on the electrical properties of silver wires and the mechanism of thermal sintering and plasma sintering were studied.The sintering mechanism of silver nanoparticles is proposed:The sintering mechanism of silver nanoparticles is proposed:the thermal sintered and plasma sintered silver first decomposes under the action of heat transfer and plasma active substances,respectively,then the silver nanoparticles were reduced and sintered.By analyzing the chemical composition of the silver wire,it can be determined that the effect of plasma sintering is better than that of thermal sintering.Under the combined action of thermal sintering and plasma sintering,the resistivity of the silver wire can reach 6×10^-8Ω·m,which is only 3.6 times that of bulk silver.更多还原