36-GHz static digital frequency dividers in AlInAs-GaInAs HBT technology

Static divide-by-four circuits have been fabricated that operate up to 36 GHz using AlInAs-GaInAs heterojunction bipolar transistor (HBT) IC technology processing an f/sub t/ and f/sub max/ of 110 and 73 GHz, respectively. The transistors used consisted of an abrupt emitter-base junction design which incorporated a low-temperature p-GaInAs spacer as part of the base to inhibit beryllium diffusion. The AlInAs-GaInAs HBT device layers were grown lattice-matched to semi-insulating InP substrates by solid-source molecular beam epitaxy (MBE).