That is, the method of manufacturing the resonance apparatus includes forming the Bragg reflector structure in addition to the operations of the method of manufacturing the resonance apparatus of FIG. 11. Therefore, the same operations as in the method of manufacturing the resonance apparatus of FIG. 11 will not be described in detail with reference to FIG. 12 for conciseness.

Referring to FIG. 12, in operation 1201, a lower electrode is formed at a predetermined distance from an upper portion of a substrate.

In operation 1202, a piezoelectric layer is formed on an upper portion of the lower electrode.

In operation 1023, a reflective layer is formed on the upper portion of the substrate. The reflective layer reflects an acoustic wave converted by the piezoelectric layer. The reflective layer may include a thickness corresponding to a wavelength of a resonance frequency of the resonance apparatus. The reflective layer may include a first reflective layer and a second reflective layer. For example, the second reflective layer may be formed by vapor depositing Mo, Ru, W, and/or Pt, on the upper portion of the substrate. In addition, the first reflective layer may be formed by vapor depositing a SiO-based material, a SiN-based material, an AlO-based material, and/or an AlN-based material, on an upper portion of the second reflective layer. A cavity is formed at an upper portion of the first reflective layer. Accordingly, the first reflective layer may include a relatively lower acoustic impedance than the second reflective layer.

In operation 1204, the upper electrode is formed on an upper portion of the piezoelectric layer.