Sub-THz RTD oscillators integrated with planar horn antennas for horizontal radiation

Fabrication and oscillation characteristics of sub-THz RTD oscillators integrated with planar horn antennas for horizontal radiation are reported. The device consists of a GaInAs/AlAs RTD, a resonator, a waveguide, and a horn antenna on a semi-insulating InP substrate. Oscillation frequency of 455 GHz and horizontal output power of ~0.6 muW were observed. The output power is small at present because of small values of the peak-to-valley current ratio and the voltage width of the negative differential resistance region of the RTD.