A monolithic grid oscillator has been fabricated that oscillates in Ka-band. The grid consists of 36 heterojunction bipolar transistors (HBT's) at intervals of 1 mm. The grid was built on a 740 pm thick GaAs substrate with gold evaporated on the back side. The oscillation frequency is 34.7 GHz, with an effective radiated power (ERP) of 170 mW at a DC bias power of 370 mW. The is the first report of a successful monolithic grid oscillator.
"A 35 GHz hst monolithic grid oscillator", Proc. SPIE 1929, 17th International Conference on Infrared and Millimeter Waves, 19295K (14 December 1992); doi: 10.1117/12.2298317; https://doi.org/10.1117/12.2298317