ESD network comprising variable impedance discharge path

A semiconductor device, comprising:

• a semiconductor substrate;
• a ground line electrically coupled to the semiconductor substrate;
• a protected line;
• a triggered clamp electrically coupling the protected line to the ground line;
• and
• a variable shunt electrically coupled between the protected line and the ground line, and parallel to the triggered clamp, the variable shunt including a depletion mode junction field effect transistor (JFET) having a drain region in the substrate, wherein the drain region is contiguous with the semiconductor substrate, wherein a gate of the depletion mode JFET includes a well in the substrate, the well having an opposite conductivity type from the semiconductor substrate.

A method, comprising:

• providing a semiconductor substrate of a semiconductor device, the semiconductor substrate having a first conductivity type;
• forming a gate of a depletion mode junction field effect transistor (JFET) in the semiconductor substrate, the gate having a second conductivity type, opposite from the first conductivity type, wherein a drain of the depletion mode JFET is contiguous with the semiconductor substrate;
• forming an electrical connection between the semiconductor substrate and a ground line of the semiconductor device;
• forming an electrical connection between a source of the depletion mode JFET and a protected line of the semiconductor device;
• and
• forming a triggered clamp in the semiconductor device, the triggered clamp being electrically coupled between the protected line and the ground line, and parallel with the depletion mode JFET.

A semiconductor device comprising:

• a semiconductor substrate having a first conductivity type;
• a gate of a depletion mode junction field effect transistor (JFET) in the semiconductor substrate, the gate having a second conductivity type, opposite from the first conductivity type, wherein a drain of the depletion mode JFET is contiguous with the semiconductor substrate;
• an electrical connection between the semiconductor substrate and a ground line of the semiconductor device;
• an electrical connection between a source of the depletion mode JFET and a protected line of the semiconductor device;
• and
• a triggered clamp in the semiconductor device, the triggered clamp being electrically coupled between the protected line and the ground line, and parallel with the depletion mode JFET.