Polishing pad and methods relating thereto
AssigneeRodel, Inc.
InventorsLee Melbourne Cook, David B. James, William D. Budinger
Life of this patent
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Abstract
A chemical-mechanical polishing system which is particularly well suited for use in the manufacture of semiconductor devices or the like. The invention is directed to a self-dressing, hydrophilic polishing pad capable of releasing particles during polishing. Such a pad design is very efficient in providing polishing particles over the entire polishing surface interface. Since the polishing pad produces polishing particles, the polishing fluid can comprise very low loadings of polishing particles, if any.
Claims18
A method of polishing, comprising:
- placing a polishing fluid having 0-2 weight percent particulate matter into an interface between a polishing pad and a substrate, the substrate containing at least one of silicon, gallium arsenide, silicon dioxide, tungsten, aluminum, and copper, the polishing pad having a surface layer, the surface layer comprising:
- a self-dressing matrix containing a plurality of particles, the matrix having a modulus in the range of 1 to 200 MegaPascals, a critical surface tension greater than or equal to 34 milliNewtons per meter, and an elongation to break in the range of 25% to 1000%, the matrix having a planar polishing surface with a surface area that is engagable with the substrate during polishing, and a three dimensional surface texture defining at least one flow channel in the polishing surface, whereby as the matrix wears during polishing, the surface area of the polishing surface changes by less than 25%, and the particles having an average aggregate diameter of less than 0.5 microns, the matrix being free of any particles greater than or equal to 1 micron in diameter, whereby as the particles separate from the matrix during polishing of the substrate, the matrix diminishes in increments of less than 1 micron.
A polishing system comprising:
- a polishing pad having a surface layer, the surface layer comprising a self-dressing matrix containing a plurality of particles, the matrix having a modulus in the range of 1 to 200 MegaPascals, a critical surface tension greater than or equal to 34 milliNewtons per meter, and an elongation to break in the range of 25% to 1000%, the matrix having a planar polishing surface with a surface area that is engagable with a substrate during polishing, and a three dimensional surface texture defining a plurality of flow channels each extending to a respective depth below the polishing surface, whereby as the matrix wears to one half the depth of a largest said flow channel, the surface area of the polishing surface changes by less than 25%, and the particles having an average aggregate diameter of less than 0.5 micron, the matrix being free of any particles greater than or equal to 1 micron in diameter, whereby as the particles separate from the matrix during polishing of the substrate, the matrix diminishes in increments of less than 1 micron.
A polishing pad comprising a surface layer, the surface layer comprising a self-dressing matrix which diminishes into a plurality of particles during polishing, the particles having an average aggregate diameter of less than 1 micron, the matrix being free of any particles greater than or equal to 1 micron in diameter, the matrix having a polishing surface with a surface area that is engagable with a substrate during polishing, and a three dimensional surface texture, whereby as the matrix wears during polishing, the surface area of the polishing surface changes by less than 25%, the matrix comprising at least one of urethane, carbonate, amide, sulfone, vinyl chloride, acrylate, methacrylate, vinyl alcohol, ether, ester and acrylamide moieties.
Dependencies are inferred from the claim text.