Disclosed is a low cost contact and interconnect layer and method for
fabricating the same. A contact via is opened within an insulating layer,
exposing a circuit node (e.g., transistor active area within a
semiconductor substrate). The via is filled with a chemical vapor
deposited (CVD) titanium silicide layer, forming electrical contact with
the circuit node. The silicide layer may simultaneously form the
interconnect layer for one embodiment. In other embodiments, the
interconnect layer may comprise a metal strap over the titanium silicide
layer, or a metal layer over an etched-back titanium silicide plug in the
contact via. For any of these embodiments, the contact via may be opened
after the formation of interconnect trenches, the via extending from the
bottom of a trench to the circuit node. CVD provides good step coverage of
the via within the trench, despite the higher aspect ratio. The
interconnect layer is deposited and etched back, such that the
interconnect lines are defined by the trenches.