Design of mm-Wave Slow-Wave-Coupled Coplanar Waveguides

• Published in: IEEE transactions on microwave theory and techniques Vol. 68; no. 12; pp. 5014 - 5028
• Main Authors: Margalef-Rovira, Marc, Lugo-Alvarez, Jose, Bautista, Alfredo, Vincent, Loic, Lepilliet, Sylvie, Saadi, Abdelhalim A., Podevin, Florence, Barragan, Manuel J., Pistono, Emmanuel, Bourdel, Sylvain, Gaquiere, Christophe, Ferrari, Philippe
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.12.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE); Institute of Electrical and Electronics Engineers
• Subjects: Band theory; BiCMOS integrated circuits; CMOS; CMOS/bipolar complementary metal–oxide–semiconductor (BiCMOS) technology; Coplanar waveguides; Couplers; coupling coefficient; directional couplers; Engineering Sciences; Frequencies; Integrated circuit modeling; Mathematical models; Micro and nanotechnologies; Microelectronics; Microstrip; Millimeter waves; Semiconductor device modeling; slow-wave concept; Strips; Topology; coupling coefficient; slow-wave concept; directional couplers; CMOS/BiCMOS technology
• DOI: 10.1109/TMTT.2020.3015974
• ISSN: 0018-9480

This article focuses on the design of high-performance coupled slow-wave coplanar waveguide (CS-CPW) in CMOS technologies for the millimeter-wave (mm-wave) frequency bands. First, the theory as well as the electrical model of the CS-CPW are presented. Next, the analytical approach for the calculation of the model parameters is discussed. Then, by using the developed model, two mm-wave backward directional 3-dB couplers are designed in a bipolar complementary metal-oxide-semiconductor (BiCMOS) 55-nm technology for 120- and 185-GHz operation, respectively. Simulation and experimental results demonstrate that the use of the CS-CPW concept leads to state-of-the-art performance, with a good agreement between the analytical model, electromagnetic simulations, and measurement results.