Abstract: In recent years, there has been an exponential growth in wireless communication systems. This is basically due to the manufacture of small size and high performance devices. Many communication devices such as filter, duplexer and oscillator require resonator as a key component. Acoustic resonators have become a key technology of growing wireless field as the propagation velocity of acoustic wave is almost five times lower than the electromagnetic waves thus resulting in small size devices. BAW resonator can be used as narrow band filter in radio-frequency applications.