Millimeter-wave slow-wave Si-benzocyclobutene transmission line: modeling and a coupler application

A millimeter-wave slow-wave transmission line (T-line) implemented with Si-benzocyclobutene (Si-BCB) technology is modeled in this paper. An artificial neural network (ANN) is applied to map the numerical relationship between the geometric parameters of the slow-wave T-line and its S-parameters. The Levenberg–Marquardt algorithm and Gradient Descent Back-Propagation optimization method are used during ANN training process. A 30-GHz coupler based on the proposed slow-wave structure is fabricated and measured. The ANN results, electromagnetic (EM)-simulated results, and measured results are consistent with one another.