A film bulk acoustic resonator includes a substrate (101); a lower electrode (110) formed on top of the substrate (101); a piezoelectric membrane (113) formed on top of the lower electrode (110) and having a crystallographic axis (CC) so inclined as to generate a total reflection when an acoustic wave advances toward the lower electrode (110); and an upper electrode (115) formed on top of the piezoelectric membrane (113). The circumference of the piezoelectric membrane (113) may comprise an enveloping wall (117) which may be patterned on the same layer as that of forming the upper electrode (115).