Millimeter-Wave Bandpass Filters by Standard 0.18- $\mu\hbox {m}$ CMOS Technology

Millimeter-wave (mm-wave) bandpass filters are presented using the standard 0.18-mum CMOS process. Without any postprocessing steps, thin film microstrip (TFMS) structure is properly constructed on the low-resistivity silicon substrate, aiming at reducing the substrate loss and crosstalk to a large extent. Using the broadside-coupled scheme, a tight coupling is achieved so as to make up a class of low-loss and broadband TFMS bandpass filters in the mm-wave range. To achieve a small size, one-stage and two-stage filters with sinuous-shaped resonators are designed and fabricated. A good agreement between the predicted and measured results has been observed up to 110 GHz