Low clamp voltage ESD device and method therefor

A low clamp voltage ESD device comprising:

• a semiconductor substrate of a first conductivity type having a first doping concentration, the semiconductor substrate having first and second surfaces;
• a first semiconductor layer of a second conductivity type on the first surface of the semiconductor substrate, the first semiconductor layer having a second doping concentration and having a first surface that is opposite to the first surface of the semiconductor substrate;
• a first semiconductor region of the second conductivity type positioned between a first portion of the first semiconductor layer and the first surface of the semiconductor substrate, the first semiconductor region having a first thickness and a third doping concentration that is greater than the second doping concentration wherein the first semiconductor region forms a zener diode with dopants of the semiconductor substrate;
• a second semiconductor region of the first conductivity type and a fourth doping concentration that is greater than the second doping concentration formed on the first surface of the first semiconductor layer and overlying a first portion of the first semiconductor region wherein the second semiconductor region forms a first P-N diode with the first semiconductor layer;
• and
• a first conductor extending from the first surface of the first semiconductor layer through the first semiconductor layer and intersecting the first semiconductor region, the first conductor adjacent to and spaced a first distance from the second semiconductor region wherein the first distance is no greater than the first thickness of the first semiconductor region wherein the first conductor forms a conduction path for current to flow from the first P-N diode to the zener diode.