Structure and method for RESURF diodes with a current diverter

A semiconductor device, comprising:

• a semiconductor substrate of a first conductivity type;
• first and second surface terminals laterally spaced-apart on a surface above the semiconductor substrate;
• a first semiconductor region of the first conductivity type overlying the substrate and ohmically coupled to the first terminal;
• a second semiconductor region of a second opposite conductivity type overlying the substrate ohmically coupled to the second terminal and laterally arranged with respect to the first semiconductor region;
• a parasitic vertical device comprising the first semiconductor region and the substrate;
• a third semiconductor region of the first conductivity type in proximity to the second semiconductor region and ohmically coupled to the second terminal, thereby forming in combination with the second semiconductor region a shorted base-collector region of a lateral transistor extending between the first and second terminals;
• a buried layer of the second conductivity type located between the substrate and the first, second and third semiconductor regions;
• and
• a buried layer contact region of the second conductivity type extending from the buried layer to the surface to permit electrical contact to the buried layer.

A semiconductor device, comprising:

• a semiconductor substrate of a first conductivity type;
• first and second surface terminals laterally spaced-apart on a surface above the semiconductor substrate;
• a first semiconductor region of the first conductivity type overlying the substrate and ohmically coupled to the first terminal;
• a second semiconductor region of a second opposite conductivity type overlying the substrate ohmically coupled to the second terminal and laterally arranged with respect to the first semiconductor region;
• a parasitic vertical device comprising the first semiconductor region and the substrate;
• and
• a third semiconductor region of the first conductivity type in proximity to the second semiconductor region and ohmically coupled to the second terminal, thereby forming in combination with the second semiconductor region a shorted base-collector region of a lateral transistor extending between the first and second terminals;
• wherein:
• the first region of the first semiconductor type comprises a first highly doped contact region ohmically coupled to the first terminal and a less highly doped body region of the first conductivity type underlying the first highly doped contact region;
• the second region of the second semiconductor type comprises a second highly doped contact region ohmically coupled to the second terminal and a less highly doped well region of the second conductivity type underlying the second highly doped contact region.

A lateral device for providing diode action on a semiconductor substrate of a first conductivity type, comprising:

• a buried layer of a second conductivity type different than the first conductivity type overlying the substrate;
• further semiconductor regions overlying the buried layer and having a surface spaced apart from the buried layer;
• a first contact region of the first conductivity type in the further semiconductor regions overlying the buried layer and extending to the surface;
• a second contact region of the second conductivity type in the further semiconductor regions overlying the buried later, laterally disposed with respect to the first contact region, and extending to the surface;
• a first terminal ohmically coupled to the first contact region;
• a second terminal ohmically coupled to the second contact region;
• a vertical parasitic device embodying the first contact region, a portion of the further semiconductor regions and the substrate;
• a channel region of the first conductivity type separating the first and second regions at the surface;
• a gate electrode overlying the channel region;
• an isolation region extending downward from the surface between an edge of the gate electrode and a third semiconductor region;
• and
• a third contact region of the first conductivity type in the further semiconductor regions in proximity to the second contact region and ohmically coupled thereto and to the second terminal, thereby forming in cooperation with the second contact region a shorted base-collector region of a lateral transistor extending between the first and second terminals.

A lateral device for providing diode action on a semiconductor substrate of a first conductivity type, comprising:

• a buried layer of a second conductivity type different than the first conductivity type overlying the substrate;
• further semiconductor regions overlying the buried layer and having a surface spaced apart from the buried layer;
• a first contact region of the first conductivity type in the further semiconductor regions overlying the buried layer and extending to the surface;
• a second contact region of the second conductivity type in the further semiconductor regions overlying the buried later, laterally disposed with respect to the first contact region, and extending to the surface;
• a first terminal ohmically coupled to the first contact region;
• a second terminal ohmically coupled to the second contact region;
• a vertical parasitic device embodying the first contact region, a portion of the further semiconductor regions and the substrate;
• a third contact region of the first conductivity type in the further semiconductor regions in proximity to the second contact region and ohmically coupled thereto and to the second terminal, thereby forming in cooperation with the second contact region a shorted base-collector region of a lateral transistor extending between the first and second terminals;
• and
• a buried layer contact region of the same conductivity type as the buried layer, extending through the further semiconductor regions from the buried layer toward the surface.