Technology Computer-Aided Design (TCAD) Feasibility Study of Scaling SiGe HBTs

Abstract

Technology computer-aided design (TCAD) feasibility studies for for scaling a SiGe-based NPN with cutoff frequencies, fT/fMAX of 200/250GHz were conducted, in which the critical process and device design components were self-consistently addressed. The calibrated 200/250GHz calibration was verified by utilization for scaling to a 300GHz performance level, which was subsequently used as the baseline for scaling to a 500 and 630GHz fT performance level. Comparison of the transit time components reveal the base and collector-base transit times as being the predominant electron delay components for performance levels less than 500GHz. At 630GHz the device was observed to be limited primarily by the collector-base transit time.