A low-loss quartz-based cross-coupled filter integrated onto low-resistivity silicon

This paper presents a 10-GHz cross-coupled bandpass filter integrated onto low-resistivity silicon. The filter is fabricated on a quartz substrate and then mounted onto the silicon using benzocyclobutene and inverted microstrip interconnects. The approach enables the integration of low-loss distributed microwave components onto CMOS-grade Si substrates while occupying a small effective footprint on the silicon. Experimental and theoretical results are given for 10-GHz filters integrated onto a 10-Ω·cm silicon substrate.