| 摘要 |
PURPOSE:To enhance a reliability to a heat cycle by a method wherein protrusions are provided on the peripheral parts of a chip or at one side or the both sides of two sites on a substrate to oppose to the chip and the interval between the surfaces of the chip and the substrate is regulated. CONSTITUTION:Bump electrodes 2 are provided on the central part of a chip 1 and protruded bodies 5 are provided on the four corners in the peripheral parts of the chip 1. The protruded bodies 5 consist of solder in the same manner as the bump electrodes 2, but are higher than the bump electrodes 2. This chip 1 is placed on an insulating substrate 3 facing downward the surfaces of the bump electrodes 2 in such a way that the bump electrodes 2 oppose over wiring conductor layers 4 coated with solder layers 41 on the substrate 3. At that time, as the protruded bodies 5 are higher, the bump electrodes 2 do not come into contact to the solder layers 41, but when they are heated, the chip 1 sinks when the protruded bodies 5 are welded to solder layers 61 and the bump electrodes 2 come into contact with the solder layers 41. As a result, the coupling parts 7 between the bump electrodes 2 and the solder electrodes 41 are expanded and are formed in a snare drum form. |
