An electronic device assembled using a coupler which has an electroconductive region and a resin region on the surface. Flexibility of the resin region absorbs stress caused by difference in thermal expansion coefficient between an organic printed circuit board and a semiconductor chip through the deformation of the electroconductive region. As a result, formation of cracking in the coupler is avoided. It is preferable that the resin region occupies from 20 to 80% of the total surface area of the coupler. The coupler may be formed from a molten blend of the heat resistant resin and a joining metal. The coupler may also be formed by molding a blend of the heat resistant resin and metal powder, wherein the metal powder locating on the surface of the coupler have a joining metal joined thereto.