Fabrication of monolithic 1-Chip FBAR duplexer for W-CDMA handsets

FBAR Filters and duplexers have high power handling capability, high Q factors, good thermal stability, a low volum, a low cost and IC compatibility their applications have been gradually increased in RF systems. However, there is no published papers and research about FBAR 1-Chip duplexer, which was fabricated with Tx and Rx filters because that is a very challenging task. We report for the first time that a monolithic 1-chip RF filter is achieved with the size of 2.5 mm × 2.5mm using a suspended membrane thin film bulk acoustic resonator (FBAR) technology to meet stringent demand for miniaturization and monolithic integration of duplexers in RF communication systems. In this work, a novel 1-Chip duplexer is designed by EM(Electromagnetic) simulation and RF Circuit simulation using HFSS and ADS. . The highest insertion losses in the pass-band (1920–1980, 2110–2170 MHz) are measured below 3.5 dB. In the Rx band(2110–2170 MHz) the attenuation is the over 45 and the attenuation in the Rx band is the over 54dB.