Synthesized high-impedance CMOS thin-film transmission line

Abstract

A synthetic quasi-TEM CMOS transmission line (TL) of wide range characteristic impedance from 58.3 to 95 Omega is presented for miniaturization of CMOS RFIC. The synthetic TL consists of unit cells made of complementary-conducting strips (CCS) and connecting arm for signal interface residing on the M5 and M1 metal layers of a typical 0.25 mu m 1P5M CMOS process. Measured results and theoretical data indicate that the loss per guiding Wavelength of the meandered CCS TL is about 13 % lower than that of the meandered microstrip of characteristic impedance 86.4 Omega at 40 GHz.