Patent ID: 6943426

Claim:
A semiconductor structure comprising: a semiconductor substrate; an epitaxial layer formed over said substrate, said epitaxial layer having a background doping concentration; first and second trenches extending downward from a surface of said epitaxial layer so as to define a mesa between said first and second trenches, each of said first and second trenches having a sidewall and a bottom, said bottom of each of said first and second trenches being located in said epitaxial layer, each of said trenches being at least partially filled with a dielectric material; and a well of dopant extending downward from said surface of said epitaxial layer to said substrate at a location between said first and second trenches, said well having a doping concentration different from said background doping concentration of said epitaxial layer, said well forming first and second junctions with a remaining portion of said epitaxial layer, said first junction extending from said bottom of said first trench to said substrate, said second junction extending from said bottom of said second trench to said substrate.