Packaging of THz circuits using a HDPE lens and an impedance-matched carrier substrate

A concept a for low-cost and robust packaging is presented. It is applied to a resonant tunneling diode (RTD) circuit fabricated on an InP substrate. The RTD circuit has been designed for wireless data transfer in the 300 GHz frequency range. The proposed system uses a substrate integrated lens made of high density polyethylene (HDPE) and a λ/4 matching layer to match the different wave impedances of HDPE and InP. The matching layer also works as a carrier substrate for the baseband circuit. The system has a simulated directivity of 21 dBi and a measured 3-dB bandwidth of 17 GHz.