Reducing wire erosion during damascene processing
AssigneeInternational Business Machines Corporation
InventorsJeffrey P. Gambino, Anthony K. Stamper
Life of this patent
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Abstract
A damascene process incorporating a GCIB step is provided. The GCIB step can replace one or more CMP steps in the traditional damascene process. The GCIB step allows for selectable removal of unwanted material and thus, reduces unwanted erosion of certain nearby structures during damascene process. A GCIB step may also be incorporated in the damascene process as a final polish step to clean up surfaces that have been planarized using a CMP step.
Claims20
A method of reducing erosion in a damascene process, comprising the steps of:
- arranging a first layer in a trench in a dielectric formed on a substrate and directly on a surface of the dielectric adjacent to the trench;
- depositing a bulk conductor on the first layer in the trench and adjacent to the trench;
- and
- selectively removing an upper portion of the bulk conductor with a gas cluster ion beam (GCIB) process that is selective to the bulk conductor by impacting large clusters of preselected types of atoms on the upper portion of the bulk conductor to be removed,
- wherein the GCIB process exposes a surface portion of the first layer that is arranged directly on the surface of the dielectric adjacent to the trench such that an upper surface of the surface portion is coplanar with an upper surface of the bulk conductor in the trench.
A method of a damascene process, comprising the steps of:
- forming a trench in a dielectric formed on a substrate;
- arranging a liner material on surfaces of the trench and directly on an upper surface of the dielectric adjacent the trench;
- forming a bulk conductor on the liner material in the trench and over the upper surface of the dielectric;
- removing an upper portion of the bulk conductor with a chemical mechanical polishing (CMP) process to expose a surface portion of the liner material directly on the upper surface of the dielectric adjacent the trench, wherein an upper surface of the surface portion is coplanar with an upper surface of the bulk conductor within the trench;
- after the CMP process, removing the surface portion of the liner material and a portion of the bulk conductor with a gas cluster ion beam (GCIB) process;
- and
- adjusting a chemistry of the GCIB process such that GCIB process selectively removes the liner material and removes the portion of the bulk conductor.
A method of forming an interconnect on a film comprising a trough, comprising the steps of:
- arranging a barrier material on a dielectric comprising a trench;
- arranging a conductor on the barrier material;
- removing, in a first process, an upper portion of the conductor to expose a surface portion of the barrier material that is directly on an upper surface of the dielectric adjacent to the trench, wherein after the first process an upper surface of the surface portion of the barrier material is coplanar with an upper surface of the conductor in the trench;
- removing, in a second process after the first process, at least a portion of the surface portion of the barrier material and a portion of the conductor by directing a gas cluster ion beam onto a material to be removed;
- and
- adjusting a chemistry of the gas cluster ion beam such that the gas cluster ion beam selectively removes the barrier material and removes a portion of the conductor.
Dependencies are inferred from the claim text.