通孔柱银浆用超细银粉的制备研究

Research on Fabrication of Ultrafine Silver Powders for Via Fill Silver Paste

通孔银浆料是低温共烧陶瓷(LTCC)基板配套的系列电子浆料中必不可少的一种材料,对银粉有很高的要求。用抗坏血酸还原体系制备银粉,研究硝酸银溶液浓度、p H值、还原剂浓度对银粉形貌及粒度分布的影响,采用扫描电子显微镜对制备的银粉进行表征分析,选取3种不同类型的银粉调制成通孔银浆进行匹配性试验。结果表明,均一性、分散性良好且平均粒径为2.0μm的球形银粉具有较好的应用潜力。

Via fill silver paste is one of the essential electronic pastes using on low temperature co-fired ceramic （LTCC） substrate, and LTCC require high quality silver powders. Ascorbic acid was used as the reducing agent. The influence of concentration of AgNO3, pH of solution, and the concentration of ascorbic acid on the morphology and size distribution of silver powders were investigated. The obtained silver powders were characterized by scanning electron microscope （SEM）. Three types of silver powders were chosen for preparing via fill silver pastes, and their matching experiment were carried out. The results revealed that highly uniform and dispersive spherical silver powders with the average size of 2.0μm have the potential for application in via fill silver pastes.