Optimization of Ge-Dose and Doping in Base of SiGe HBTs

The present work gives an approach to optimize the base doping and Ge-dose in SiGe HBTs using the fixed point iterative methodology and includes the effect of minority carrier velocity saturation on total base transit time for SiGe HBTs. It is shown that shifted-Ge profile approach and triangular Ge-profile in base can lead to simultaneous optimization of Ge-dose and base dopant distribution for minimum base transit time.