2D numerical simulation for InGaP/GaAs HBT safe operating area

The safe operating area (SOA) of InGaP/GaAs heterojunction bipolar transistors (HBT) has been studied using two-dimensional (2D) Technology Computer-Aided Design (TCAD) tool. The hydrodynamic transport based impact ionization and self-heating models were implemented. The DC simulation result shows two distinct SOA boundary regimes corresponding to different dominant mechanisms, which is in good agreement with analytical modeling and experimental results. The simulation not only gives us insight to the detailed failure mechanisms but also provides guidance for the design of devices with better ruggedness and improved SOA performances.