Abstract: A surface elastic wave device is provided in which an influence of the stress based on a difference of the coefficients of thermal expansion between the surface elastic wave chip and a wiring substrate is reduced and a connection defective due to heat is prevented. When quartz is used for a surface elastic wave substrate (K1) and aluminum is used for the wiring substrate (52), the surface elastic wave device is characterized in that bumps are arranged within a definite area (B1) in aluminum pads (input electrode pad (4), output electrode pad (5), and ground electrode pads (G1 to G8)) placed on a functional surface of the surface elastic wave chip (1). According to the present invention, an area in which the bumps are formed, a film thickness of an aluminum pad (Al film thickness), the chip size of the surface elastic wave chip (1), and the number of the bumps are defined to a surface elastic wave substrate of quartz or LiTaO3.

Abstract: A resin sealing structure according to the invention has convex parts formed in the vicinities of the perimeters of elements on a substrate to prevent thereby the resin, when it is applied for sealing, from invading the wiring parts of the elements. There may be narrow enough gaps between the substrate and the elements not to allow the resin to enter. This structure enables resin sealing to be accomplished at a high yield and dispenses with metallic caps or the like.