纳米银填充导电浆料的研究进展

Review of Recent Advances in Nano-Silver-Filled Conductive Pastes

导电浆料是发展电子元器件的基础及封装、电极和互联的关键材料。随着电子元器件向微型化、精密化和柔性化等方向发展,国内外正在开展金属导电填料纳米化的研究。其中,纳米银填充导电浆料成为该领域的研究热点。纳米银作为导电填料对银浆性能影响是正面还是负面影响还没有一个统一的结论。一般认为纳米银填充到基体中,由于粒子间的接触点面积小,填料粒子数目增多导致接触电阻增加。只有当纳米银间距离在一定范围内时,由于隧道效应等使导电性增强。这主要与其颗粒大小和形貌、表面性质和烧结行为等密切相关。本文从纳米银填充导电浆料的导电机理、纳米银低温烧结、表面处理、填量、形貌和原位添加等方面综述了国内外研究者近年来在纳米银填充导电浆方面的研究进展,并对未来的发展方向进行了展望。

Conductive pastes are the foundation of the development of electronic components and the key materials in the fields of the encapsulation, electrodes and interconnect. With the miniaturization and precision and flexibility of electronic components, the researches on nano-metal conductive fillers are carrying out both at home and abroad. The nano-silver-filled conductive pastes have always been a focus of research in this field. The positive or negative effects of nano- silver filler on conductive pastes are still uncertain. It was found that when nano-silver particles were added into the matrix, the contact resistance increased in almost cases because nano-silvers contain a larger number of particles that are beneficial to the interconnection between particles. The electrical conductivity was increased due to the tunnel effect only when the distance between nano-silver is in a certain range. This is closely related to particle size and morphology, the surface properties and sintering behaviors, etc. In this review, some recent advances in the nano-silver filled conductive pastes, such as conductive theory, low temperature sintering, surface treatment, nanoparticle size and morphology, and in situ formation of nano-silver, are presented. The prospects for the development of nano-silver filled conductive pastes are also discussed.