US 6,281,135 B1 · Oxygen free plasma stripping process

Abstract

A method for stripping photoresist and/or removing post etch residues from an exposed low k dielectric layer of a semiconductor wafer in the presence or absence of copper. The method comprises creating an oxygen free plasma by subjecting an oxygen free gas to an energy source to generate the plasma having electrically neutral and charged particles, The charged particles are then selectively removed from the plasma. The electrically neutral particles react with the photoresist and/or post etch residues to form volatile gases which are then removed from the wafer by a gas stream. The oxygen free, plasma gas composition for stripping photoresist and/or post etch residues comprises a hydrogen bearing gas and a fluorine bearing wherein the fluorine bearing gas is less than about 10 percent by volume of the total gas composition.

Claims23

Dependent claims

A method for ashing photoresist 16 and/or post etch residues from a substrate 98 subsequent to an etching procedure comprising:

a. placing at least one substrate 98 having photoresist 16 and/or post etch residues thereon into a wafer processing chamber 22;
b. forming a reactive species by generating a plasma in the absence of oxygen wherein a gas for generating said plasma comprises a hydrogen bearing gas and a fluorine bearing gas;
and
c. selectively removing the photoresist 16 and/or the etch residues including sidewall polymer depositions from an underlying layer in contact with the photoresist and/or post etch residues at a removal rate greater than a rate of removal of the underlying layer by exposing the substrate to said reactive species wherein said reactive species are essentially electrically neutral.

1 more element

Dependencies are inferred from the claim text.

Oxygen free plasma stripping process

Life of this patent

Oxygen free plasma stripping process

Life of this patent

Abstract

Claims23