A W-band tripler with a novel band pass filter on thin-film substrate

The novel multilayer thin-film substrate using BCB as a dielectric was suggested in the paper. 3-metals and 2-BCB layers were used in this technology for the evaluation of passive devices. The band pass filter for W-band application with unique circuit and structure was designed and implemented. The implemented filter has an insertion loss below 1.5 dB, and return loss over 20 dB in the passband of 90~100 GHz. The attenuation is over 40 dB and 20 dB at the first and second harmonic frequencies, respectively and this response is adequate for the tripler application. The W-band tripler with a novel band pass filter in output part was evaluated on the thin-film substrate using commercial 0.15 um GaAs pHEMT from WIN foundry, and occupies the area of 2.5 x 1.5 mm. The measured response shows the conversion gain of -20dB and the spurious suppressions are 20 dBc and 10 dBc for the first and second harmonics, respectively due to the operation of the band pass filter.