Patent ID: 7060619

Claim:
A method of forming conductors over a semiconductor body having a top surface in which electrical contact areas are formed comprising the steps of: forming a first inorganic insulating layer having a first value of k over the top surface; forming vias completely through the first inorganic insulating layer which are in contact with the contact areas; filling the vias through the first inorganic insulating layer with conductive material to form conductive plugs which contact the contact areas; forming a first dielectric insulating layer having a second value of k over the first inorganic insulating layer, said second value of k being lower than said first value of k; forming trenches in the first dielectric insulating layer from a top surface thereof; lining the trenches in the first dielectric insulating layer with a conductive barrier liner layer; filling the trenches in the first dielectric insulating layer with copper to at least a level of a top surface of the first dielectric insulating layer; removing a portion of the copper fill in the trenches so as to recess the copper in the trenches from the top surface of the first dielectric insulating layer; applying a conductive activation layer of Pd over the top surface of the recessed copper; electrolessly and selectively depositing a conductive barrier layer over the conductive activation layer in the trenches, said conductive barrier layer having a top surface which is essentially planar with the top surface of the first dielectric insulating layer, the conductive barrier layer on the top surface of the recessed copper selected from a group consisting of CoP, Co, Ni, NiP, W, Ru, Mo, Cr, Re, V, Mn, Zn, Sn, Pb, and combinations thereof, to work as a Cu diffusion barrier; forming a second dielectric insulating layer having the second value of k over and directly contact with the first dielectric insulating layer; forming vias and trenches in the second dielectric insulating layer and lining same with a conductive barrier liner layer, copper filling, copper recessing, conductive activation applying, and forming a conductive barrier layer over a conductive activation layer as was done with respect to the first dielectric insulating layer; and forming a second inorganic insulating layer having a relatively high k over a top surface of the second dielectric insulating layer.