US 10,096,496 B2 · Process chamber for etching low K and other dielectric films

Abstract

Methods and process chambers for etching of low-k and other dielectric films are described. For example, a method includes modifying portions of the low-k dielectric layer with a plasma process. The modified portions of the low-k dielectric layer are etched selectively over a mask layer and unmodified portions of the low-k dielectric layer. Etch chambers having multiple chamber regions for alternately generating distinct plasmas are described. In embodiments, a first charge coupled plasma source is provided to generate an ion flux to a workpiece in one operational mode, while a secondary plasma source is provided to provide reactive species flux without significant ion flux to the workpiece in another operational mode. A controller operates to cycle the operational modes repeatedly over time to remove a desired cumulative amount of the dielectric material.

Claims18

Dependent claims

A method of etching a dielectric film, the method comprising:

loading a workpiece into an etch chamber;
modifying a top thickness of the dielectric film disposed on the workpiece by bombarding the workpiece with a low energy flux of non-reactive ions from a capacitively coupled plasma of a first source gas energized within a first chamber region, wherein the first chamber region is between a chuck supporting the workpiece and a first showerhead;
etching the modified top thickness of the dielectric film selectively over the dielectric film disposed under the top thickness by exposing the workpiece to a reactive species generated by a plasma of a second source gas energized in a second chamber region, wherein the second chamber region is disposed above the showerhead, opposite the chuck;
cyclically repeating both the modifying and etching until an etch process termination criteria is met;
and
unloading the workpiece from the etch chamber.

3 more elements

Dependencies are inferred from the claim text.

Process chamber for etching low K and other dielectric films

Life of this patent

Process chamber for etching low K and other dielectric films

Life of this patent

Abstract

Claims18