Used In The Preparation And Study Of The Electronics Industry Fine Silver Powder And Silver Paste

This thesis contents two parts, research on preparation technology of ultrafine silver powder and formulation of conductive silver paste.As one of the most commonly used precious metal powder, the preparation and performance of silver powder are concerned at home and abroad. In this thesis, by using liquid chemical deposition method, silver nitrate as raw material, hydrazine hydrate as reducing agent, polyvinylpyrrolidone(PVP) as disperse agent, ultrafine silver powder was prepared by dropping silver nitrate into reducing solution at room temperature, and then separated by filtrating with millipore filter. The products were characterized by TEM, XRD and Particle Sizing Systems, and the effects of concentration of PVP and AgNO3 on the size and yield of ultrafine silver powders were also studied. This novel preparation technology enjoys a good application prospect for the advantages of high purity and uniform technical index as compared to traditional mechanical preparation method.The development of microelectronic chip modules and packaging brings high requirements on industrial process conditions and environmental protection, thus the conductive paste has been used widely. The conductive silver paste which used ultrafine silver powder as main component occupies an important position. In this thesis, different ratios of components of epoxy resin based conductive silver paste were attempted to study their relations to properties of silver paste, and a species of conductive silver paste were developed with high performance and environment-friendly property. The product can be used for LED packaging, electromagnetic shielding and other fields.