The resin used as the underfill comprises epoxy resin, phenol resin and silicone resin alone or as a mixture of two or more of them which may be blended optionally with a filler such as silicon dioxide or aluminum oxide, coupling agent, colorant or flame retardant. [0121] In addition, as shown in FIG. 10, the semiconductor device 9 (semiconductor chip) and the multi-layered wiring substrate 6 may