用于电子封装的纳米银浆低温无压烧结连接的研究

用纳米银浆在低温无压条件下烧结获得了铜与铜的互连,这一接头制造过程可以替代钎料应用于电子封装中。在150℃～200℃烧结温度下,接头强度为17 MPa～25 MPa,热导率为54 W/（m.K）～74 W/（m.K）。柠檬酸根作为保护层包覆在纳米颗粒表面起到稳定作用。保护层与纳米颗粒之间形成的化学键断裂是烧结过程发生的开始。通过透射电镜观察发现了一种新的由于有机保护层不完全分解产生的松塔状纳米银颗粒烧结再结晶形貌。讨论了这种再结晶形貌对接头导热性能产生的影响。

Pressureless Low Temperature Sintering of Ag Nanoparticles Applied to Electronic Packaging

Report a Cu-to-Cu interconnects fabrication process based on the pressureless low temperature sintering of Ag nanoparticles,which could be applied for replacing soldering in electronic packaging.The shear strength of joints reached 17~25 MPa at temperatures ranging from 423 K to 473 K.And the thermal conductivity of sintered Ag nanoparticles reached 54~74 W/（m.K）.The organic shells of citrates covered on the nanoparticels stabilized the Ag nanoparticles.The chemical bonds that connected the organic shells with Ag nanoparticles were broken for sintering to take place.A novel pineconelike recrystallization morphology of sintered Ag nanoparticles was observed by TEM（transmission electron microscopy）,which resulted from the incompletely thermal decomposition of organic shells.The effect of recrystallization morphology on the thermal conductivity of sintered Ag nanoparticles was discussed.