Slow-wave coplanar waveguides in a printed circuit technology

Abstract

In this paper, slow-wave coplanar waveguides, well-known to present a high degree of miniaturization and a high quality factor in CMOS technology, are investigated in a classical printed circuit board technology. These transmission lines are measured between 45 MHz and 4 GHz. An effective relative permittivity greater than 13 can be reached for a 50-Ω characteristic impedance transmission line, leading to a slow-wave factor higher than 2. Additionally, low characteristic impedance transmission lines can be obtained without critical dimensions compared to classical coplanar waveguides. Thus, these results allow considering the design of highly miniaturized RF printed circuits based on transmission lines.