Geometry scalable model parameter extraction for mm-wave SiGe-heterojunction transistors

The observation of negative perimeter collector current in advanced SiGe HBT technologies is explained and a general geometry scaling approach is proposed. Application to mm-wave SiGe-HBTs shows excellent results of HICUM/L2 v2.31 for a wide range of emitter dimensions. Non-monotonic variation of peak f
_T
with emitter dimensions demonstrates the relevance of a geometry scalable compact model for circuit optimization.