US Patent 7285830 Lateral bipolar junction transistor in CMOS flow

An improved lateral bipolar junction transistor and a method of forming such a lateral bipolar transistor without added mask in CMOS flow on a p-substrate are disclosed. The CMOS flow includes patterning and n-well implants; pattern and implant pocket implants for core nMOS and MOS; pattern and implants pocket implants I/O nMOS and pMOS; sidewall deposit and etch and then source/drain pattern and implant for nMOS and pMOS. The bipolar transistor is formed by forming emitter and collector contacts by implants used in source/drain regions; forming an emitter by implants done in core pMOS during core pMOS LDD extender; and forming part of an base by pocket implant steps.