Surface acoustic wave device, method for manufacturing, and electronic circuit device
View Patent ↗A surface acoustic wave device which occupies a small mounting area and has a low profile, yet having an improved reliability, and can be made available at low cost. The surface acoustic wave device comprises a piezoelectric substrate, a function region formed of comb-like electrodes for exciting surface acoustic wave provided on a main surface of the piezoelectric substrate, a space formation member covering the function region, a plurality of bump electrodes provided on a main surface of the piezoelectric substrate and a terminal electrode provided opposed to the main surface of piezoelectric substrate. The bump electrode and the terminal electrode are having a direct electrical connection, and a space between piezoelectric substrate and terminal electrode is filled with resin. When the above-configured acoustic wave device is applied for a frequency filter, a resonator, in a portable telephone unit, a keyless entry or the like communication apparatus, the overall size of such apparatus can be reduced and a higher reliability is implemented.
1. A surface acoustic wave device comprising:
a piezoelectric substrate,
a comb-like electrode provided on a main surface of said piezoelectric substrate,
a space formation member provided on said comb-like electrode portion,
a plurality of bump electrodes provided on said main surface of said piezoelectric substrate, and
a plurality of terminal electrodes coupled to said plurality of bump electrodes, respectively
the piezoelectric substrate and the terminal electrodes are resin-sealed to form a sealed body, wherein a main face of each of said terminal electrodes are exposed and a side face of each of the terminal electrodes is flush with one of a plurality of side surfaces of the sealed body.
2. The surface acoustic wave device of claim 1 , wherein
in a bottom surface of said sealed body, another main face of said terminal electrode is flush with a bottom surface of the sealed body.
3. The surface acoustic wave device of claim 1 , wherein
in a bottom surface of the sealed body, a resin between said terminal electrodes is protruding from another main face of said terminal electrode.
4. The surface acoustic wave device of claim 1 , in a bottom surface of the sealed body, another main face of said terminal electrode is protruding from a bottom surface of the sealed body.
5. The surface acoustic wave devices of claims 2 through 4 , wherein
a thickness of said terminal electrode is thicker in an area outer than a place of connection with said bump electrodes relative to a rest of the area.
6. The surface acoustic wave device of claim 1 , wherein
said space formation member is formed of a wall and a lid, and disposed covering said comb-like electrode portion.
7. The surface acoustic wave device of claim 6 , further comprising a conductor island disposed opposed to the lid, another main surface of said conductor island being exposed in a surface of a sealed body.
8. The surface acoustic wave device of claim 7 , wherein
the lid and the conductor island are glued with an adhesive agent.
9. The surface acoustic wave device of claim 7 , wherein
the lid and the conductor island are glued with a resin constituting the sealed body.
10. The surface acoustic wave device of claim 1 , wherein
said space formation member is formed of an wall and a conductor island provided making contact with said wall at a top edge to constitute a cover, and another main surface of the conductor island is exposed in a surface of a sealed body.
11. The surface acoustic wave device of claim 10 , wherein
the top edge of the wall is attached pressed to the conductor island.
12. The surface acoustic wave device of claim 10 , wherein
the top edge of the wall and the conductor island are glued with an adhesive agent applied on at least one item among the top edge of the wall and the conductor island.
13. The surface acoustic wave device of claim 7 or claim 10 , wherein
said another main surface of the conductor island is flush with said another main face of said terminal electrode.
14. The surface acoustic wave device of claim 7 or claim 10 , wherein
said another main surface of the conductor island and said another main face of said terminal electrode are flush with a surface of the sealed body.
15. The surface acoustic wave device of claim 7 or claim 10 , wherein
said terminal electrode and said another main surface of the conductor island are disposed at a position hollowed from the surface of the sealed body.
16. The surface acoustic wave device of claim 7 or claim 10 , wherein
said terminal electrode and said another main surface of the conductor island disposed protruded from the surface of the sealed body.
17. The surface acoustic wave device of claim 7 or claim 10 , wherein
a thickness of said terminal electrode is thicker in an area outer than a place of connection with said bump electrodes relative to a rest of the area.
18. The surface acoustic wave device of claim 7 or claim 10 , wherein
the conductor island is electrically connected with at least one of said terminal electrodes.
19. The surface acoustic wave device of claim 1 , wherein
a material of said bump electrodes contains at least one metal among the group of gold, tin, copper, lead and silver.
20. The surface acoustic wave device of claim 7 or claim 10 , wherein
said terminal electrode and the conductor island are made of a layer formed of a material containing gold as a main content, or a laminated layer formed of a material containing gold as the main content and a metal material other than gold.
21. An electronic circuit device comprising:
a surface acoustic wave device including
piezoelectric substrate,
a comb-like electrode provided on a main surface of said piezoelectric substrate,
a wall surrounding said comb-like electrode portion,
a plurality of bump electrodes provided on said main surface of said piezoelectric substrate, and
a plurality of terminal electrodes coupled to said plurality of bump electrodes, respectively,
wherein the piezoelectric substrate and the terminal electrodes are resin-sealed to form a sealed body,
wherein a main face of each of said terminal electrodes are exposed and a side face of each of the terminal electrodes is flush with one of a plurality of side surfaces of the sealed body; and
a circuit board provided with a wiring conductor line, wherein
said surface acoustic wave device is mounted on said circuit board and the terminal electrodes of said surface acoustic wave device are connected with said wiring conductor line.
22. The electronic circuit device of claim 21 , wherein
an electronic component or a semiconductor component is mounted or contained in at least one of said circuit board and an inside of said circuit board.
23. The electronic circuit device of claim 21 , wherein
at least said surface acoustic wave device is covered with a resin on said circuit board.