Copper electroplating apparatus
AssigneeNovellus Systems, Inc.
InventorsSteven T. Mayer, Evan E. Patton, Robert L. Jackson, Jonathan D. Reid
Life of this patent
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Abstract
An electroplating apparatus prevents anode-mediated degradation of electrolyte additives by creating a mechanism for maintaining separate anolyte and catholyte and preventing mixing thereof within a plating chamber. The separation is accomplished by interposing a porous chemical transport barrier between the anode and cathode. The transport barrier limits the chemical transport (via diffusion and/or convection) of all species but allows migration of ionic species (and hence passage of current) during application of sufficiently large electric fields within electrolyte.
Claims36
An apparatus for electroplating a metal onto a substrate, the apparatus comprising:
- a cathode electrical connection that can connect to the substrate and apply a potential allowing the substrate to become a cathode;
- an anode electrical connection that can connect to an anode and apply an anodic potential to the anode;
- and
- a porous transport barrier defining an anode chamber and a cathode chamber, which transport barrier enables migration of ionic species, including metal ions, across the transport barrier while substantially preventing non-ionic organic bath additives from passing across the transport barrier.
An apparatus for electropolishing copper on an anode substrate or electroplating copper onto a cathode substrate, the apparatus comprising:
- an anode electrical connection that can connect to the anode and apply an anodic potential to the anode;
- a cathode electrical connection that can connect to a cathode and apply an cathodic potential to the cathode;
- and
- a transport barrier defining an anode chamber and a cathode chamber, which transport barrier enables migration of ionic species, including copper ions, across the transport barrier,
- wherein the apparatus maintains a catholyte in the cathode chamber and an anolyte in the anode chamber, and wherein the viscosity of the catholyte is maintained at a substantially lower value than the viscosity of the anolyte.
An apparatus for electroplating copper onto a substrate, the apparatus comprising:
- separate anode and cathode chambers ionically connected to one another;
- an anolyte flow loop that circulates anolyte into, out of, and through the anode chamber;
- a catholyte flow loop that circulates catholyte into, out of, and through the cathode chamber, wherein the apparatus substantially prevents anolyte and catholyte from mixing and maintains different compositions of anolyte and catholyte, and
- a porous transport barrier separating the anode chamber from the cathode chamber, which transport barrier enables migration of ionic species, including copper ions, across the transport barrier while substantially preventing non-ionic organic bath additives from passing across the transport barrier.
An apparatus for electroplating copper onto a substrate, the apparatus comprising:
- separate anode and cathode chambers ionically connected to one another;
- an anolyte flow loop that circulates anolyte into, out of, and through the anode chamber;
- a catholyte flow loop that circulates catholyte into, out of, and through the cathode chamber, wherein the apparatus substantially prevents anolyte and catholyte from mixing and maintains different compositions of anolyte and catholyte;
- an anolyte make up subsystem that periodically delivers anolyte to at least one of the anolyte flow loop and anode chamber, and
- a porous transport barrier separating the anode chamber from the cathode chamber, which transport barrier enables migration of ionic species, including copper ions, across the transport barrier while substantially preventing non-ionic organic bath additives from passing across the transport barrier.
Dependencies are inferred from the claim text.