| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a solder paste capable of suppressing occurrence of voids even in a substrate having a minute print area such as a solder bump, and also, capable of preventing long-term reliability from drastically deteriorating due to progress of cracks starting from the voids caused by thermal strain and impact in a reliability test after mounting to the substrate. <P>SOLUTION: The solder paste is formed by improving a paste for forming a bump which is made of solder powder and flux composed of rosin, an activator, a solvent, and a thickener, and in which the content of the solder powder in the paste is 85-95 wt.%. The paste is used for forming a bump by a pattern film printing method for mounting an FC. When the paste is measured under desired conditions by a TG method, the weight reduction rate of the paste is≤1.0% at a temperature higher than a liquidus-line temperature of the solder by 25°C,≤1.5% at a temperature higher than the liquidus-line temperature by 50°C, and viscosity of the paste is≥60 Pa s <250 Pa s. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
