| 摘要 |
PURPOSE:To improve a yield rate, by covering a substrate, on which circuit element are mounted, with a mixed resin of thermosetting resin and ultravilet- ray setting resin, heating the resin, decomposing the resin into a gel shaped resin, projecting ultraviolet rays, and hardening the surface layer. CONSTITUTION:A conducting plate 3 is attached to the lower surface of a substrate 1. A conducting pattern 2 is formed on the upper surface. A semiconductor chip 5 is connected to the conducting plate 3 with conducting paste 4 and also connected to the conducting pattern 2 with bonding wires 6. In order to protect such a substrate, the surface is covered with a mixed resin of thermosetting resin and ultraviolet-ray setting resin. The resin is heated and decomposed into a gel shaped resin 8. Then ultraviolet rays (a) are projected and the surface is hardened. Thus, a solid state resin 9 is obtained. In this way, faults such as cracks in the chip 5 and the resin layer and breakdown of the bonding wires can be prevented, and the yield rate can be improved. |
