Trench poly ESD formation for trench MOS and SGT

Abstract

A semiconductor device and its method of fabrication are described. A trench formed in a semiconductor substrate is partially filling said trench with a semiconductor material that lines a bottom and sides of the trench, leaving a gap in a middle of the trench running lengthwise along the trench. A first portion of the semiconductor material located below the gap is doped with dopants of a first conductivity type. The gap is filled with a dielectric material. Second portions of the semiconductor material located on the sides of the trench on both sides of the dielectric material are doped with dopants of a second conductivity type. The doping forms a P-N-P or N-P-N structure running lengthwise along the trench with differently doped regions located side by side across a width of the trench.

Dependencies are inferred from the claim text.