FBAR

An integration process for the fabrication of thin film bulk acoustic wave resonator (FBAR) above the CMOS IC is proposed. An adhesive-bonding-based film transfer technique is utilized to transfer high resistivity Si film onto a CMOS chip. Benzocyclobutene (BCB) is used as an adhesive film. It is a heat resistive polymer and processes of temperature up to 300 C are allowed on it. The CMOS is protected by BCB and thus is not damaged by plasma and chemical treatments.