【作者】 黄涛；

【导师】 曾晓雁；

【作者基本信息】 华中科技大学 ， 物理电子学， 2009， 硕士

【摘要】 随着电子产品向小型化、柔性化方向发展,传统的微米级导电浆料已不能满足当前电子元器件对更低加工温度和更小特征尺寸的要求。开发适应低热处理温度、小尺寸加工工艺的纳米银导电浆料/墨水已经成为导电浆料发展的必然趋势。然而当前这种纳米银导电浆料/墨水的研究和生产还主要集中在一些发达国家,在我国相关研究才刚刚起步。因此,开展纳米银导电浆料/墨水的研究、制备有着重要的意义。首先,本文介绍了化学还原法制备纳米银颗粒的原理,以硼氢化钠为还原剂,月桂酸为保护剂,通过还原银氨络合物制备出了纳米银颗粒。探讨了不同还原剂、保护剂及其浓度等对制备效果的影响。该法制备工艺简单,制备出的纳米银颗粒纯度高,粒径集中分布于5-30nm,平均粒径为17nm。然后,以自制的纳米银粉为导电功能相,以司班-85、松油醇、乙基纤维素等为有机载体的主要成分,制备出了纳米银导电浆料。研究了纳米银导电浆料的配方和相应的混合及分散工艺。制备的纳米银浆料分散均匀且粘度高,可在300℃以下烧结成形。对该浆料进行初步的微笔直写实验,制备的线条宽度最小可达120μm,烧结后导线的标准方阻为6.1m?/□。最后,以固体颗粒在液相中的分散机理为依据,探讨了不同分散剂和相关助剂对纳米银颗粒在水中的分散稳定性的影响,确定了以OP-10乳化剂为分散剂的纳米银导电墨水的配方及分散方法。实验结果表明,制备出的纳米银导电墨水导电相含量可达28%wt,均匀性好,并可在300℃进行烧结,烧结后的膜层具有一定的导电性。更多还原

【Abstract】 With the development of miniaturization and flexibility of electronic products, the traditional micro-conductive paste can not match the process of lower sintering temperature and smaller feature size in current fabrication of electronic components. The trend will be made to develop nano-silver paste/ink suiting for low heat-processing temperature and fine fabrication feature size. However, most of the research work about the nano-silver paste/ink was dedicated in the developed country, and little effort has been made in China. It is significant to develop nano-silver paste/ink in our country.Firstly, the mechanisms of preparing nano-silver particles with chemical reduction -protection method were introduced. The nano-silver particles were prepared from the reduction of silver-ammonia complex, taking sodium borohydride as reducing agent, and dodecanoic acid as dispersing agent. The influence of the dispersing and reducing agent on the preparation was explored. The diameters of the prepared silver particles from this process were mostly ranging from 5nm to 30nm, and the average size was about 17nm.Secondly, the nano-silver paste was formulated with the as-synthesized nano-silver particles as conductive phase, the mixture of Span-85, terpineol and ethyl cellulose as organic vehicle. The formula and the dispersing process of the paste were explored. The prepared nano-silver paste with uniform dispersion and high viscosity could be sintered at 300℃. The width of the conductive line was the minimum of 120μm, obtaining from the preliminary micro-pen direct-writing test, and its standard sheet resistance was about 6.1m? /□.Finally, according to the dispersing mechanism of solid particles in liquid phase, the effects of dispersants and additives on the nano-silver dispersing stability were testified. The dispersing method and nano-ink formula were decided with emulsifier OP-10 as the disperse agent. The prepared uniform ink was 28% in solid content, and could be sintered at 300℃. The coatings had certain conductivity.更多还原