Characterization of a Flexible Polymer-Based Substrate Material for RF Applications

While mechanically flexible substrate materials are widely used in electronics, especially for interconnects between moving system parts or medical sensors to be mounted onto the body surface, they are barely used in micro- and millimeter-wave applications. In this work, the design permittivity of a low-cost, polymer-based flexible substrate is extracted by measurement and the insertion losses of typical line structures are measured. Moreover, application examples of a patch antenna and a bendable substrate-integrated waveguide are presented.