In an exemplary method a piezoelectric wafer is prepared on which multiple piezoelectric frames are formed. Each frame has a piezoelectric vibrating piece including excitation electrodes, and a frame portion surrounds the vibrating piece. A lid wafer is prepared on which multiple respective lids are formed, each sized substantially similarly to the respective frames. A base wafer is prepared on which multiple of bases are formed, each sized substantially similarly to the respective frames. Each base has through-holes. Stripes of a first bonding film are formed on both major surfaces of the piezoelectric wafer around the periphery of each frame. Stripes of a second bonding film are formed on the inner major surface of the lid wafer, corresponding to respective stripes of the first bonding film. Stripes of a third bonding film are formed on the inner major surface of the base wafer, corresponding to respective stripes of the first bonding film. A bonding material is placed between the stripes of first bonding film and respective stripes of second bonding film, and between stripes of first bonding film and respective stripes of third bonding film, by which the three wafers are bonded together after being aligned with each other in a sandwich manner.