Method for mounting surface acoustic wave element and surface acoustic wave device having resin-sealed surface acoustic wave element

A surface acoustic wave device comprising:

• an individual surface acoustic wave element being cut out of a plurality of surface acoustic wave elements each of which has a comb electrode formed on a piezoelectric substrate and being flip-mounted on a single common substrate using a bump in such a manner as the comb electrode is disposed opposite to the common substrate,
• wherein, in a state of being mounted on the common substrate, the plurality of surface acoustic wave elements are covered by a first resin layer, and a second resin layer formed on the first resin layer, and
• the first resin layer and the second resin layer are thermosetting resins in which state transitions of being softened and thereafter cured are produced through heating process, and
• the first resin layer is formed of a resin material having greater fluidity caused by softening than the resin material of the second resin layer.

A surface acoustic wave device comprising:

• a substrate;
• a surface acoustic wave element having a comb electrode formed on a piezoelectric substrate, and being flip-mounted on the substrate using a bump in such a manner as the comb electrode is disposed opposite to the substrate;
• a heat-resistant laminating frame laminated on the substrate, and positioned so as to surround the surface acoustic wave element;
• and
• a resin layer for covering the surface acoustic wave element,
• wherein the resin layer is a thermosetting resin in which state transitions of being softened and thereafter cured are produced through heating process, and
• the resin layer seals the comb electrode by adhering to the side faces of the surface acoustic wave element and the upper face of the laminating frame.

A method for mounting a surface acoustic wave element comprising:

• flip-mounting, on a substrate, the surface acoustic wave element having a comb electrode formed on a piezoelectric substrate using a bump in such a manner as the comb electrode is disposed opposite to the substrate;
• fixing a resin sheet formed of a first resin layer of thermosetting resin in which state transitions of being softened and thereafter cured are produced through heating process and a second resin layer formed on the first resin layer, in which the first resin layer is formed of a resin material having greater fluidity caused by softening than the resin material of the second resin layer;
• and
• airtight sealing the comb electrode by pressing the resin sheet with heat at a predetermined temperature.