纳米银与纳米铜混合焊膏用于电子封装低温烧结连接

Low temperature sintering-bonding using mixed Cu+Ag nanoparticle paste for packaging application

摘要: 文中提出将纳米银焊膏与纳米铜焊膏按照一定比例进行混合,研究其烧结特性及其用于低温烧结连接镀银的铜块.结果表明,多元醇法制得的纳米银+纳米铜混合焊膏具有良好的防氧化特性;在5 MPa压力并保温5 min条件下,摩尔比例为1:1的混合焊膏在烧结温度为250℃时,接头抗剪强度最大并达到22 MPa.随混合焊膏中纳米银颗粒含量增加,接头强度逐渐增大;纯纳米铜颗粒焊膏的接头抗剪强度为15 MPa,纯纳米银焊膏的接头强度可到达56 MPa.

Abstract: In this study,the two kinds of nanoparticle pastes were prepared by using the modified polyol chemical reduction process,respectively,and the mixed nanoparticle paste was prepared by mechanically mixing of the two pastes. The sintering characteristics of the mixed paste were investigated,and the results show that the mixed paste had good oxidation resistance. Ag-coated copper bulks were bonded through the sintering of mixed paste. The results indicate that the increasing of Ag content in the paste was beneficial to high quality of joints,and with the bonding conditions of sintering at 250℃ for 5 min under 5 MPa pressure,the average shear strengths of joints using nano- Cu paste,mixed paste consisting of 50% mole Ag and 50% mole Cu,and nano-Ag paste,were 15 MPa,22 MPa and 56 MPa,respectively.