High-voltage tolerant device and detection circuit

A high-voltage device, comprising:

• a semiconductor substrate of a first type, having a surface;
• a deep well of a second type formed on the surface, wherein the second type is opposite to the first type;
• a field isolation layer formed on the surface and above the deep well, separating a drain active region from a source active region;
• a control gate formed on top of the field isolation layer, serving as a gate electrode of the high-voltage device;
• a first well of the second type, wherein the source active region at least partially overlaps the first well, the first well extends below the field isolation layer, and the first well at least partially overlaps the control gate;
• and
• a buried layer of the first type embedded within the semiconductor substrate, formed at a bottom of the deep well and having an extensive portion below the control gate;
• wherein the deep well provides a conductive channel that allows current to flow from the drain active region, and across the deep well and the first well beneath the field isolation layer, reaching the source active region.