Patent ID: 7911022

Claim:
A high voltage device, comprising: a substrate; two heavily doped regions of a second conductivity type in the substrate; at least two isolation regions in the semiconductor substrate and between the two heavily doped regions; a heavily doped region of a first conductivity type disposed in the substrate and between the two isolation regions; a dielectric layer on the heavily doped region of the first conductivity type; a metal layer separated from the heavily doped region of a first conductivity type by the dielectric layer, wherein a portion of the metal layer overlies a portion of the dielectric layer overlying the heavily doped region of a first conductivity type, and at least a portion of the metal layer directly overlies the dielectric layer, the heavily doped region of the first conductivity type and the at least two isolation regions; and a diffusion region of the first conductivity type surrounding the heavily doped region of the first conductivity type and disposed between the heavily doped regions of the second conductivity type, wherein the metal layer is not electrically connected to the doped region of the first conductive type.