Optimized flip-chip interconnect for 38 GHz thin-film microstrip multichip modules

Flip-chip interconnects with 80 /spl mu/m bumps are optimized for 38 GHz by means of electromagnetic simulation. Thin-film microstrip is used as transmission-line on the carrier substrate. A compensation structure reduces reflections at the interconnect below -20 dB. Measurements of a passive structure and active chip modules proved the feasibility of this approach.