Design and Manufacturing of a Miniaturized 2.45GHz Bulk Acoustic Filter by High Aspect Ratio Etching Process
C-H Lin, H-R Chen, C-H Du and W. Fang
National TsingHua University, TW
Keywords: bulk acoustic device, ICP, MEMS resonator
A 2.45GHz filter is fabricated by thin film bulk acoustic wave resonator (FBAR) technology. Especially, it is designed to minimize die size and to simplify fabrication process simultaneously by using inductive coupling plasma etching. The quality factor (Q) and electromechanical coupling coefficient (K2) of a single resonator were 1567 and 5.7% respectively, which were derived through measured phase and amplitude of input impedance. The fabricated filter has minimum insertion loss around 1.5dB and maximum insertion loss 3.6dB in 83.5MHz bandwidth, which is suitable for WLAN and Bluetooth applications.
Nanotech 2004 Conference Technical Program Abstract