Gas mixture for removing photoresist and post etch residue from low-k dielectric material and method of use thereof
AssigneeLam Research Corporation
InventorsCristian Paduraru, Alan Jensen, David Schaefer, Robert Charatan, Tom Choi
Life of this patent
Estimating the term…
Abstract
Atomic oxygen generated in oxygen stripping plasmas reacts with and damages low-k dielectric materials during stripping of dielectric post etch residues. While damage of low-k dielectric materials during stripping of dielectric post etch residues is lower with hydrogen stripping plasmas, hydrogen stripping plasmas exhibit lower strip rates. Inclusion of oxygen in a hydrogen stripping plasma improves both photoresist strip rate and uniformity, while maintaining a hydrogen to oxygen ratio avoids low-k dielectric material damage.
Claims14
A method of removing photoresist and post etch residue from a semiconductor substrate having a layer of low-k dielectric material comprising:
- introducing a semiconductor substrate having a layer of low-k dielectric material having photoresist and post etch residue thereon into a downstream reaction chamber;
- generating plasma comprising reactive species in an upstream applicator, wherein the reactive species comprise atomic hydrogen and atomic oxygen, wherein atomic oxygen passivates applicator surfaces exposed to the plasma, wherein the plasma is generated from a gas mixture comprising 0.05-0.1% by volume oxygen, 1-10% by volume hydrogen, and balance inert carrier gas and
- introducing the reactive species into the downstream reaction chamber, wherein atomic hydrogen removes photoresist and post etch residue from the low-k dielectric material.
Dependencies are inferred from the claim text.