An improved P+/N diode leakage current in BiCMOS technologies with fluorine co-implant

Fluorine (F) is a co-implant species known to have numbers of beneficial effects to the semiconductor device. In this study, we demonstrate the effect of fluorine to the p+/n-junction leakage current improvement in BiCMOS technologies. In which, fluorine and boron fluoride (BF₂) were used instead of fluorine-boron (F-B) or BF₂ only. By changing the implant sequence at P+ region from F followed by BF₂ to BF₂ followed by fluorine (BF₂-F), the leakage current improved by one decade with a higher breakdown voltage also observed in the reverse sequence, BF₂-F.