Abstract: A composite assembly of a relatively inexpensive ceramic, such as alumina, with a skin, or covering, of a high wear ceramic, such as sapphire, adapted to be used in industrial environments subjected to high levels of corrosion and/or erosion. The design life of the composite assembly may be significantly longer than previously used components. The composite assembly may have its ceramic pieces joined together with aluminum, such that the joint is not vulnerable to corrosive aspects to which the composite assembly may be exposed.

Abstract: Improved method and apparatus for removing material from a surface of a workpiece including a low dielectric constant material are disclose. The apparatus includes a platen, having a polishing surface attached thereto, configured to orbit at more than about 500 revolutions per minute and a workpiece carrier configured to rotate and apply about 0.25 to about 2 psi. to the workpiece in the direction of the platen.

Abstract: A method for planarizing the surface of a wafer against a polishing pad includes the steps of securing the wafer in a carrier, pressing the wafer against the polishing pad, rotating both the wafer and pad, and moving the wafer across the polishing pad to create one or more geometric patterns relative to the pad. Geometric patterns employed by the present method include a ‘figure eight’, an elliptical pattern, and a peanut-shaped pattern. In one embodiment of the invention, both a ‘figure eight’ pattern and an elliptical pattern are used during a single planarizing operation. Bezier splines (curves) are used to create geometric patterns employed by the planarizing process.