Recent advances in the performance of InP Gunn devices and GaAs TUNNETT diodes for the 100-300-GHz frequency range and above

Improved heat dissipation in InP Gunn devices resulted in RF power levels e xceeding 200, 130, 80, and 25 mW at oscillation frequencies of around 103, 132, 152, and 162 GHz, respectively. Corresponding dc-to-RF conversion effi ciencies exceeded 2.3% from 102 to 132 GHz, Power combining increased the a vailable RF power levels to over 300 mW at 106 GHz, around 130 mW at 136 GH z, and more than 125 mW at 152 GHz with corresponding combining efficiencie s from 80% to over 100%, Operation in a second harmonic mode yielded RF pow er levels of more than 3.5 mW at 214 GHz, over 2 mW around 220 GHz as well as over 1 mW around 280, 300, and 315 GHz, RF power levels exceeding 10 mW at 202 GHz, 9 mW around 210 GHz, and 4 mW around 235 GHz were obtained from GaAs TUNNETT diodes in a second harmonic mode as well. Corresponding dc-to -RF conversion efficiencies were around 1% at 202 and 210 GHz.