Buried multilevel interconnect system

摘要

A method and apparatus for providing interconnections between levels on a semiconductor substrate of various types includes first forming a plurality of trenches in the substrate and then forming conductive layers at the bottom of the trenches. The trenches are then filled with an oxide to provide a planar surface on the substrate. Various levels of trenches are provided with crossovers being formed by a bridging layer of a conductive material that is formed over an oxide layer in the lower level trenches. Vertical contacts are formed by etching an opening from the surface to the bottom of the trenches through the oxide layer and filling the opening with a metal plug.