  Terahertz technology is largely dependent upon planar on-chip antennas that
radiate downwards through the substrate, and so an effective means to interface
these antennas with integrated waveguides is an attractive prospect. We present
a viable methodology for backside coupling between a terahertz oscillator chip
and a broadband all-intrinsic-silicon dielectric waveguide. Our investigation
employs resonant tunneling diodes as compact two-terminal electronic terahertz
oscillators, and terahertz waves are observed from 270 GHz to 409 GHz. The fact
that this power is accessed via a curved length of silicon waveguide validates
successful backside coupling.
