Coplanar waveguides in silicon with low attenuation and slow wave reduction

This paper presents coplanar waveguide structures with low attenuation and slow-wave reduction implemented in standard silicon technologies and suitable for frequencies of up to 40 GHz. Optimization and modelling of slow-wave coplanar waveguides (SW-CPW) is provided here and compared to standard CPW models. An on-chip SW-CPW attenuation of 0.25 dB/mm at 40 GHz is obtained, compared with 2.8 dB/mm for a standard CPW. As an application, a non-linear transmission line (NLTL) was designed using SW-CPW sections. This NLTL can sharpen the pulse rise time by 75%. This work demonstrates the feasibility and advantage of using SW-CPW techniques to build all-silicon pulse-compression NLTLs using commercial silicon foundry processes.