公开(公告)号：US20050269385A1

公开(公告)日：2005-12-08

申请号：US10859207

申请日：2004-06-03

申请人： Sinn-Wen Chen ,  Shih-Kang Lin ,  Ching-Feng Yang ,  Yu-Chih Huang ,  Ting-Ying Chung ,  Ying-Mei Tsai ,  An-Ren Zi

发明人： Sinn-Wen Chen ,  Shih-Kang Lin ,  Ching-Feng Yang ,  Yu-Chih Huang ,  Ting-Ying Chung ,  Ying-Mei Tsai ,  An-Ren Zi

IPC分类号： B23K31/02 ,  B23K35/02 ,  B23K35/26 ,  C22C13/02 ,  H01L21/60 ,  H05K3/34

CPC分类号： H05K3/3463 ,  B23K35/0238 ,  B23K35/26 ,  B23K35/262 ,  C22C13/00 ,  H01L24/81 ,  H01L2224/13609 ,  H01L2224/16 ,  H01L2224/8121 ,  H01L2224/81815 ,  H01L2924/01005 ,  H01L2924/01006 ,  H01L2924/01013 ,  H01L2924/01029 ,  H01L2924/01033 ,  H01L2924/01047 ,  H01L2924/01049 ,  H01L2924/0105 ,  H01L2924/01078 ,  H01L2924/01079 ,  H01L2924/01082 ,  H01L2924/01322 ,  H01L2924/01327 ,  H01L2924/014 ,  H01L2924/15747 ,  Y10T428/12493 ,  H01L2924/00

摘要： This invention forms an indium or indium alloy layer on top of a Sn based lead-free solder. The indium or indium alloy layer can be formed by various methods, such as plating, deposition, printing, dipping, etc. The indium-containing layer melts during the soldering process, wets the substrate, and forms a sound solder joint. Since the melting point of indium is 156.6° C., even lower than that of the eutectic Sn—Pb which is at 183° C., so the soldering process can be carried out at a temperature lower than the conventional soldering process. During the soldering process, the indium reacts with the Sn based Pb-free solder alloy. Since the eutectic temperature of Sn—In is at 120° C., during the short time of the soldering process, the surface of the In deposited Pb-free solder remains as the liquid phase and have a good wetting with the substrate, while a In gradient is formed in the In deposited Pb-free solder.

摘要翻译： 本发明在Sn基无铅焊料的顶部形成铟或铟合金层。 可以通过电镀，沉积，印刷，浸渍等各种方法形成铟或铟合金层。在焊接工艺期间，含铟层熔化，润湿基板，形成良好的焊点。 由于铟的熔点为156.6℃，甚至低于在183℃的共晶Sn-Pb的熔点，所以焊接工艺可以在比常规焊接工艺低的温度下进行。 在焊接过程中，铟与Sn基无铅焊料合金反应。 由于Sn-In的共晶温度为120℃，在焊接过程的短时间内，In沉积的无铅焊料的表面保持为液相，并且与衬底具有良好的润湿性，而 在In沉积的无铅焊料中形成梯度。