Method of forming a high capacitance diode

A method of forming a high capacitance zener diode comprising:

• providing a semiconductor substrate of a first conductivity type;
• forming a semiconductor layer of a second conductivity type overlying the semiconductor substrate, the semiconductor layer having a first doping concentration and a surface;
• forming a first region of the first conductivity type overlying the surface of the semiconductor substrate, the first region having a second doping concentration that is greater than the first doping concentration;
• and
• forming a semiconductor channel extending from within the first region through the semiconductor layer and into the semiconductor substrate, the semiconductor channel having the second conductivity type and approximately the second doping concentration wherein an interface between the semiconductor channel and the first region forms a P-N junction of the zener diode.