Patent ID: 9355862
Filing Date: 2016-05-31
CPC Classification: H01J,H01L

Claim Text:
1. A method of removing titanium nitride hardmasks, the method comprising: forming a carbon-containing layer over low-k dielectric walls over an underlying copper layer on a patterned substrate, wherein the low-k dielectric walls form a trench and a via fluidly coupled to one another and the low-k dielectric walls are capped with titanium nitride hardmasks, wherein the titanium nitride hardmasks overhang the low-k dielectric walls; dry-etching the carbon-containing layer to expose the titanium nitride hardmasks leaving behind a remainder of the carbon-containing layer; placing the patterned substrate in a substrate processing region of a substrate processing chamber; flowing a radical-fluorine precursor into the substrate processing region, wherein the radical-fluorine precursor is prevented from reacting with the underlying copper layer and the low-k dielectric walls by the remainder of the carbon-containing layer; etching away the titanium nitride hardmasks, wherein an electron temperature within the substrate processing region is below 0.5 eV during the operation of etching away the titanium nitride hardmasks; and removing the remainder of the carbon-containing layer.