Microsystem Technologies

, Volume 24, Issue 5, pp 2371–2377 | Cite as

Enhancement of 5 GHz on-chip bandpass filter performance by using CMOS-MEMS inductors

  • Ja-Hao Chen
Technical Paper


We propose the use of microelectromechanical system (MEMS) inductors to enhance the performance of a 5-GHz on-chip bandpass filter. The proposed filter is implemented using the TSMC 0.18 μm one-poly six-metal (1P6M) CMOS process. For reducing substrate loss to improve filter performance, the silicon substrate underlying the filter’s MEMS inductors is removed using the Chip Implementation Center micromachining postprocess. Compared to conventional on-chip CMOS inductors on-silicon substrate, the simulation results obtained using the CMOS-MEMS inductors showed a quality factor improvement of 264.3% at 5.5 GHz. The measured insertion loss of the proposed filter with the CMOS-MEMS inductors is 3.2 dB at 4.7 GHz, and the ripple is 0.6 dB in the passband. The − 3-dB bandwidth ranges from 4.2 to 5.8 GHz. The attenuation is better than − 22 dB for frequencies ranging from 1 to 3.8 GHz and − 25 dB from 6.9 to 10 GHz in the stopband. The shape factor of the filter is 1.97:1 at an attenuation of 25/3 dB. The chip area is very small, and the optimal chip size is 1.3 × 0.75 mm2. The proposed filter could be integrated directly with the silicon base process, namely, CMOS and BiCMOS, for 5-GHz band wireless front-end applications.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2017

Authors and Affiliations

  1. 1.Department of Communication EngineeringFeng Chia UniversityTaichungTaiwan, ROC

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