Comprehensive study of ultra broadband GCPW-MS transition on thin films

Back-to-back GCPW-MS-GCPW (Grounded Coplanar Waveguide-Microstrip lines) transitions realized on benzocyclobutene polymer thin films (20 μm) and using copper metallization are presented in this article. The achieved experimental bandwidth is 82 GHz with a remarkably lower cutoff frequency of only 1.5 GHz and insertion loss of 0.5 dB. This performance is obtained without neither making via holes in the substrate nor patterning the bottom ground plane. These transitions make easier and faster manufacturing and characterization, by means of coplanar probes, of microwave devices realized from materials in thin film and whose driving electrode is a MS line. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2041–2045, 2015