Patent ID: 7795102

Claim:
A method of forming a Electrostatic Discharge (ESD) protection diode, comprising performing steps of a bipolar process used in forming a vertical bipolar junction transistor (BJT) that includes a collector, a base, and an emitter, said steps including forming a collector, forming an internal base on top of the collector, doping the internal base, and forming a polysilicon emitter region with emitter contact on top of the internal base region, the method further comprising establishing a contact to the collector, wherein the collector contact defines a contact to the ESD protection diode, blocking the formation of external base regions during the steps of the bipolar process, and doping the polysilicon emitter with the same dopant type as the internal base to establish the emitter contact as another contact to the ESD protection diode, wherein a p-n junction of the ESD protection diode is defined between the collector and the internal base of the BJT.