Patent ID: 8648419

Claim:
An electronic assembly, comprising: first and second external terminals; a core circuit coupled between the first and second external terminals; a bipolar transistor electrostatic discharge (ESD) clamp coupled between the first and second external terminals, wherein the bipolar transistor electrostatic discharge (ESD) clamp comprises: an emitter region of a first doping density electrically coupled to the first terminal, a collector region of a second doping density electrically coupled to the second terminal, a base region of a third doping density located between the emitter region and the collector region, and a further region of a fourth doping density located between the base region and the collector region, wherein at least the further region extends to an overlying dielectric-semiconductor interface; and wherein the base region has a first dopant boundary with the further region and the collector region has a second dopant boundary with the further region and wherein at least one of the first and second dopant boundaries has a maximum dopant density at a distance Y>0 beneath the dielectric-semiconductor interface.