Optimization of Si/SiGe HBT Architecture Integrated in 28-nm FD-SOI BiCMOS Technology

Abstract

This work aims to investigate a new Si/SiGe HBT in the fully depleted silicon on insulator technology (FD-SOI 28 nm). The epitaxial extrinsic base isolated from the collector (EXBIC) architecture has been used in this technology to reduce base resistance and enable cut-off frequencies to exceed 400 and 600 GHz for transition frequency f_t and maximum oscillation frequency f_max, respectively. Static and dynamic characteristics of the FD-SOI 28 nm have been evaluated using COMSOL multiphysics software. The technology achieved at base-emitter voltage of 0.83V, a value of 346 and 763.35 GHz for f_t and f_max, respectively. To further enhance frequency performance, architecture parameters such as germanium concentration, extrinsic base doping, emitter height and width are optimized achieving f_t of 360 GHz and f_max of 900 GHz. The results demonstrate the potential of using the SiGe HBTs based on the FD-SOI technology in the RF modules and THz systems.