Dual hardmask single damascene integration scheme in an organic low k ILD

A process of using an inorganic dual hardmask in a single damascene process integration scheme to allow formation of isolated single damascene features at sub 0.18 μ design rules in an organic low k interlayer for patterning of single damascene features without causing feature-to-feature short circuits due to hardmask erosion and to permit removal of photoresist in an oxidizing plasma without attack of the organic ILD materials dielectric (ILD) when making a semiconductor, comprising:

• a) providing a semiconductor substrate;
• b) depositing an organic low k ILD layer on said substrate;
• c) forming a inorganic hardmask 1 on said organic low k ILD layer and forming a sacrificial inorganic hardmask 2 on inorganic hardmask 1;
• d) forming a patterned photoresist layer on sacrificial inorganic hardmask 2;
• e) severely faceting sacrificial inorganic hardmask 2 by ion sputtering at the 90 degree corners by performing an etch selective to sacrificial inorganic hardmask 2 and stripping said photoresist with an oxygen plasma, a reagent having oxygen or a reagent of 1-methyl-2 pyrrolidine without attack of said organic low k ILD layer;
• f) performing an etch of inorganic hardmask 1 in which the etch is selective to said organic low k ILD layer;
• g) depositing a liner or conformal barrier layer over the substrate, organic low k ILD layer, inorganic hardmask 1 and sacrificial inorganic hardmask 2;
• h) forming a plated metal layer over the liner or conformal barrier layer;
• and
• i) removing said metal layer and removing said liner or conformal barrier layer with simultaneous removal of sacrificial inorganic hardmask 2 in a manner such that facets in sacrificial inorganic hardmask 2 are removed during liner/sacrificial inorganic hardmask 2 removal.