公开(公告)号：US08961709B1

公开(公告)日：2015-02-24

申请号：US10588647

申请日：2004-03-09

申请人： Kunihito Takaura ,  Kaichi Tsuruta ,  Hiroshi Kawanakago ,  Hiroshi Takahashi

发明人： Kunihito Takaura ,  Kaichi Tsuruta ,  Hiroshi Kawanakago ,  Hiroshi Takahashi

IPC分类号： B23K35/34

CPC分类号： H05K3/3484 ,  B23K35/0244 ,  B23K35/025 ,  B23K35/262 ,  C22C13/00 ,  H05K3/3463 ,  H05K2201/0272

摘要： A solder paste using a Sn—Ag base, Sn—Cu base, or similar alloy powder has a high melting point, so it causes thermal damage to electronic devices. Sn—Ag—In base lead-free solder alloys having a low melting temperature have been studied, but they are difficult to use because they cause much occurrence of chips standing up during reflow.The present invention forms a solder paste by separating a Sn—Ag—In base lead-free solder into first and second solder alloy powders for which the difference in their peak temperatures measured by differential thermal analysis is at least 10° C. and blends the mixed powders with a flux.

摘要翻译： 使用Sn-Ag基底，Sn-Cu基底或类似合金粉末的焊膏具有高熔点，因此对电子器件造成热损伤。 已经研究了具有低熔融温度的Sn-Ag-In基底无铅焊料合金，但是由于它们在回流期间引起大量的芯片堆积而难以使用。 本发明通过将Sn-Ag-In基底无铅焊料分离成通过差示热分析测量的其峰值温度差异至少为10℃的第一和第二焊料合金粉末形成焊膏，并将 混合粉末与助焊剂。