Fully encapsulated metal leads for multi-level metallization

Abstract

A method of fabricating a lead for use in conjunction with a semiconductor device and the lead. A surface is provided which is disposed on a semiconductor substrate and has a via (,) with electrically conductive material (,) therein extending to the substrate. A lead is formed on the surface having an optional barrier layer (,) disposed on the surface and contacting the electrically conductive material (,). An electrically conductive metal layer (,) is formed which is disposed over and contacting the barrier layer (,) and has sidewalls. An anti-reflective coating (,) is formed on the electrically conductive metal layer (,) remote from the barrier layer (,). The electrically conductive metal layer (,) is encapsulated between the barrier layer (,) and the anti-reflective layer (,) with a composition taken from the class consisting of TiN, W, Ti, and Si,N,. The composition is then removed except from the sidewalls of the electrically conductive metal layer (,) to encapsulate the electrically conductive layer. The electrically conductive metal layer (,) is indented relative to the barrier layer (,) and the anti-reflective layer (,) to form an I-shape with the barrier layer and the anti-reflective layer.