InP-Based Grounded Coplanar Waveguide to WR3 Transition for Monolithic Integration with THz Photodiodes

A novel monolithic integration concept of an indium phosphide (InP) THz-photodiode (PD) featuring a rectangular waveguide output is presented. The concept is based on a planar grounded coplanar waveguide to rectangular waveguide (GCPW-to-WR3) transition designed on an InP substrate. The presented integration eliminates the need for complex and high-cost hybrid integration and packaging techniques, like flip-chip, wire-bonding, and split-block. The numerical analysis of the designed transition shows a 3dB bandwidth of 44 GHz within the WR3-band. Its electrical performance and bandwidth are compared with the ultra-thin low-dielectric liquid crystalline polymer-based GCPW-to-WR3 transition.