| 摘要 |
A system for preparing a microcellular polyurethane material, includes a froth, prepared, for instance, by inert gas frothing a urethane prepolymer, preferably an aliphatic isocyanate polyether prepolymer, in the presence of a surfactant; a filler soluble in a CMP slurry; and a curative, preferably including an aromatic diamine and a triol. To produce the microcellular material, the froth can be combined with the filler, e.g., PVP, followed by curing the resulting mixture. The microcellular material has a low rebound and can dissipate irregular energy and stabilize polishing to yield improved uniformity and less dishing. CMP pads using the microcellular material have pores created by inert gas frothing throughout the pad polymer body and additional surface pores created by dissolution of fillers during polishing, providing flexibility in surface softness and pad stiffness.
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