Process for patterning metal connections on a semiconductor structure by using a tungsten-titanium etch resistant layer

Claim 1

A process for patterning a layer of conductive material formed on a semiconductor structure comprising; depositing a first layer of an alloy of tungsten and titanium on the semiconductor structure; depositing the layer of conductive material onto the first layer; removing undesired portions of the layer of conductive material by etching said layer with a plasma containing chlorine, wherein the plasma etching is substantially stopped by the first layer after etching through the layer of conductive material; removing the thereby exposed portions of the first layer with an etchant other than the plasma etchant used to etch the layer of conductive material; removing selected portions of the first layer, said selected portions lying beneath the layer of conductive material and contiguous to the edge of the layer of conductive material; and treating at least those portions of the layer of conductive material from beneath which the first layer has been removed to cause those portions to come into contact with the underlying material, the treating including forming a layer of dielectric material over the surface of the layer of selected material.