60 GHz CPW dual-mode rectangular ring bandpass filter using integrated passive devices process

A CPW dual-mode rectangular ring bandpass filter at 60 GHz using integrated passive device (IPD) process is presented in this paper. Thick metal in IPD can give lower loss for CPW. The shunt capacitor from wide underpass that maintains equal potential between two ground planes can also help to reduce the size of the ring filter. The measured center frequency of passband is 62GHz with minimum insertion loss as 2.2dB. Two transmission zeros are located at 50GHz and 80GHz. Return loss is better than 15dB around center frequency. The active filter size is 654μm × 750μm. Measurement results agreed well with EM simulation. With comparable size as on-chip bandpass filter, the IPD CPW filter provides a low cost solution for filter implementation.