| 摘要 |
<p>PROBLEM TO BE SOLVED: To inhibit an outflow of a molten solder material by a method, wherein a Pb concentration in a solder alloy material is prepared at a specified value or lower. SOLUTION: A semiconductor device 40 is constituted into a structure, wherein a semiconductor base body 21, a chip resistor 22 made of ceramics, a chip capacitor 23 and a terminal 24 are secured conductively and mechanically on a circuit board 10 of a structure, wherein a copper wiring layer 3 is selectively formed on the main surface of an Al plate 1 via an insulating resin layer 2 with a solder material 25. This solder material 25 contains two or more kinds of metals, which are selected from a group of Sn, Sb, Ag, Cu, Zn, In and Bi, and Pb as its main component. A Pb concentration in the solder material 25 is prepared at about 10wt.% or lower. Moreover, a bonding is performed on the base body 21 using a metal wire, and these mounted components 21 to 25 and the board 10 are hermetically sealed with a molding resin 30 with selected coefficient of thermal expansion of about 10 to 20ppm/ deg.C. Thereby, a thermal fatigue resistance and airtightness of soldered parts are enhanced, and a refusion of solder in a thermal process is inhibited.</p> |
