Technological requirements for a lateral SiGe HBT technology including theoretical performance predictions relative to vertical SiGe HBTs

A new class of bipolar transistors, lateral SiGe HBTs, is considered from a theoretical point of view with regard to their feasibility and potential radio frequency (RF)/microwave performance relative to existing vertical SiGe HBT technologies. Using numerical analysis, it is found that the low terminal parasitics of a lateral SiGe HBT structure can provide at least twice the unity power gain frequency f/sub max/ compared to vertical structures for a given minimum lithography. Methods to fabricate a lateral SiGe HBT with superior RF/microwave characteristics compared to existing vertical technologies are explored. Extension of the numerical analysis results using simple scaling rules reveals that it should be possible to fabricate lateral SiGe HBTs with unity power gain frequencies in the neighborhood of 500 GHz operating in the micro-ampere range.