Integrated Third-Order Millimeter-Wave On-Chip Bandpass Filter Using 0.13-µm SiGe Bi-CMOS Technology

This paper introduces an on-chip third-order bandpass filter (BPF) for millimeter-wave (mm-wave) applications. The proposed BPF is composed of three identical broadside-coupled meander-line resonators (BCMLR) which are jointly connected by three MIM capacitors through a T-shape network. The MIM capacitors are used as J-inverters for the implementation of the third-order BPF in order to achieve the desired multiple transmission poles and zeros across the passband and stopband, correspondingly. To fully understand the operational mechanism of the proposed high-order structure, the resonator and the proposed BPF are analyzed using an LC-equivalent circuit model for further investigation of the distribution of the transmission poles and zeros in terms of the metal inductance and MIM capacitance. To prove the concept, the proposed BPF prototype is implemented in a commercial 0.13-µm SiGe (Bi)-CMOS process. According to the results obtained from on-wafer measurement, three transmission poles and three transmission zeros are clearly observed. Noticeably, the proposed BPF exhibits excellent performances including a flat in-band response (less than 1 dB attenuation) from 26.7 GHz to 44.3 GHz with a measured insertion loss of 3.1 dB at the center frequency of 35.5 GHz and stopband attenuation up to 35 dB at 59 GHz. The chip size is 0.016 mm² (0.066 × 0.236 mm²), excluding the GSG pads.