Extrusion printing of radio frequency coplanar waveguides with commercial dispensing equipment

Abstract Coplanar waveguides (CPWs) are fundamental components of radio frequency and microwave circuits used for a variety of applications in telecommunications, radar systems and wireless communications. There is a need for low-cost and easily accessible manufacturing techniques that enable the fabrication of CPWs using commercial materials and equipment, thus reducing production costs and facilitating easy access to these versatile transmission lines. In this paper, we present CPWs on alumina substrates fabricated with an extrusion printing process based on low-cost commercial dispensing equipment and a commercial silver ink. For a 4 mm long CPW, we observe an insertion loss below 1 dB and a return loss better than 10 dB for the frequency range from 40 MHz to 33.8 GHz.