fT × BVcbo product modeling for SiGe:C HBTs

The specific aspects of SiGe:C HBT process and device simulation using TCAD are discussed. Cut-off frequency f T and collector junction breakdown voltage BV cbo dependences on carbon concentration in SiGe base area are investigated. The boron and carbon profiles in SiGe base are obtained to provide a trade-off between gain, cut-off frequency and break-down voltage. High values of f T × BV cbo product were achieved.