Polysilicon/metal contact resistance in deep trench

A method of forming a trench structure that includes forming a metal containing layer on at least the sidewalls of a trench, and forming an undoped semiconductor fill material within the trench. The undoped semiconductor fill material and the metal containing layer are recessed to a first depth within the trench with a first etch. The undoped semiconductor fill material is then recessed to a second depth within the trench that is greater than a first depth with a second etch. The second etch exposes at least a sidewall portion of the metal containing layer. The trench is filled with a doped semiconductor containing material fill, wherein the doped semiconductor material fill is in direct contact with the at least the sidewall portion of the metal containing layer.