| 摘要 |
<p>PURPOSE:To obtain a solder for semiconductor having a high reliability, by adding a fixed amount of Ca into a solder containing In or Pd and Sn as a main component. CONSTITUTION:Ca is added into a solder base material of Pd-Sn alloy, Pd-In alloy, et.c, in the concentration of 50-300ppm. In the concentration less than 50ppm, the solder is easily oxidized and the mechanical strength is not improved, and in more than 300ppm, the extensibility becomes lower and a strain stress caused by the difference of thermal expansibilities between the base plate and the semiconductor chip is not relaxed sufficiently. Further, the excessive mechanical strength causes a crack on the chip. As the solder has an excellent anti-thermal wearing, absorbability of strain stress and anti-oxidizability, and also it does not cause crack on the chip of breaking the junction part, highly reliable junction is obtained with this solder.</p> |
