A thin-film bulk acoustic resonator, a semiconductor apparatus including the acoustic resonator and its manufacturing method are presented. The thin-film bulk acoustic resonator includes a lower dielectric layer, a first cavity inside the lower dielectric layer, an upper dielectric layer, a second cavity inside the upper dielectric layer, and a piezoelectric film that is located between the first and second cavities and continuously separates these two cavities. The plan views of the first and the second cavities have an overlapped region, which is a polygon that does not have any parallel sides. The piezoelectric film of this inventive concept is a continuous film without any through-hole in it, therefore it can offer improved acoustic resonance performance.