Patent ID: 8723243

Claim:
A trench structure comprising: a trench in a semiconductor on insulator (SOI) substrate, wherein said trench extends from a surface of a semiconductor on insulator (SOI) layer of said SOI substrate through a buried dielectric layer of said SOI substrate into a base semiconductor layer of said SOI substrate; an undoped semiconductor material fill present in a lower portion of said trench that is located in said base semiconductor layer; a dielectric layer present on sidewalls of said trench and extending from a portion of said buried dielectric layer into said base substrate layer; a metal containing layer present on said dielectric layer, wherein a contact portion of said metal containing layer extends above an upper surface of said undoped semiconductor material fill; and a doped semiconductor material fill present in said trench extending from an upper portion of said trench that extends through said SOI layer of said SOI substrate into contact with said contact portion of said metal containing layer.