Apparatus for polishing using improved plate supports
AssigneeSpeedFam-IPEC Corporation
InventorBob McJunken
Life of this patent
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Abstract
A set of supports are advantageously disposed on a top plate having a polishing surface useful for polishing workpieces, thereby applying substantially uniform pressure to the top plate. In a preferred embodiment, the supports are non-isosceles triangular elements distributed evenly at 45 degree increments around a ring-shaped top plate. This structure effectively compensates for radial stress variations arising from non-optimum positioning of support points with respect to the inner and outer diameters of the polishing surface.
Claims12
An apparatus for polishing at least one workpiece, said apparatus comprising:
- a top plate having a bottom surface and a top surface;
- a first polishing surface provided on said bottom surface of said top plate for planarizing said at least one workpiece, wherein said first polishing surface exerts a downward force on said workpiece, and said workpiece experiences a material removal rate;
- and
- a plurality of support means secured to said top surface of said top plate for distributing said downward force such that variation of said material removal rate across said at least one workpiece surface is substantially independent of said downward force.
An apparatus for polishing at least one workpiece, said apparatus comprising:
- a top plate having a bottom surface and a top surface;
- a first polishing surface provided on said bottom surface of said top plate for planarizing said at least one workpiece wherein said first polishing surface exerts a downward force on said workpiece, and said workpiece experiences a material removal rate;
- a backing plate having a bottom surface;
- and
- a plurality of support means interposed between said top surface of said top plate and said bottom surface of said backing plate for distributing said downward force such that variation of said material removal rate across said at least one workpiece surface is substantially independent of said applied force.
Dependencies are inferred from the claim text.