摘要 |
PROBLEM TO BE SOLVED: To provide a fabrication method of a film bulk acoustic resonator that makes it possible to form a piezoelectric film which is formed on a smooth surface and has good crystallinity. SOLUTION: The film bulk acoustic resonator includes: a substrate 11; an acoustic reflector portion 14 formed on the substrate 11; and an acoustic resonator portion 18 stacked on the acoustic reflector portion 14. The acoustic resonator portion 18 includes a lower electrode 15, a piezoelectric film 16, and an upper electrode 17, which are sequentially stacked on the acoustic reflector portion 14. The acoustic reflector portion 14 includes a low acoustic impedance layer 13 comprising a material whose acoustic impedance value is lower than the acoustic impedance value of the lower electrode 15, and a layer of the acoustic reflector portion 14 in contact with the acoustic resonator portion 18 is a film formed by spin coating. COPYRIGHT: (C)2008,JPO&INPIT
|