Patent ID: 7326596

Claim:
A method for forming a high voltage semiconductor power device, comprising: providing a first dopant source of first conductivity on an upper surface of a substrate of second conductivity; providing a second dopant source of first conductivity on a lower surface of the substrate; annealing the substrate for a first given time to drive the dopants from the first and second dopants sources into the substrate; removing the first and second dopant sources from the upper and lower surfaces of the substrate; annealing the substrate for a second given time to homogenize dopant concentration within the substrate after the first and second dopant sources have been removed, the annealing the substrate for the second given time resulting in out-diffusion of dopants proximate the upper and lower surfaces of the substrate; and providing compensation dopants into the substrate after annealing the substrate for the second given time to compensate the out-diffusion of the dopants proximate the upper and lower surfaces, wherein the dopants driven into the substrate to define an isolation diffusion structure that extends from the upper surface to the lower surface.