Platen assembly having a topographically altered platen surface

In a linear polishing apparatus having a linear belt support assembly for supporting a linear belt, wherein a wafer having a diameter is pressed against one side of the linear belt, a platen comprising:

• a substantially planar surface positioned underneath the linear belt opposite the wafer, the substantially planar surface positioned in the linear belt support assembly and comprising a diameter that is greater than the diameter of the wafer, the platen further comprising a leading edge and a trailing edge, wherein the trailing edge is positioned at an opposite end of the substantially planar surface from the leading edge;
• a plurality of fluid channels disposed between the leading and trailing edges of the platen, wherein each of the fluid channels comprises a respective opening defined by the substantially planar surface;
• and
• at least one region of raised topography being symmetric about a diameter of the platen extending from the leading edge to the trailing edge and positioned closer to the trailing edge than to the leading edge, wherein the at least one region of raise topography is shaped as a continuous arc having an arc length less than 180°.

In a platen assembly for supporting a polishing member on a polishing apparatus, a platen comprising:

• a substantially planar surface positioned underneath the polishing member opposite the wafer, the substantially planar surface positioned in the support assembly and comprising a diameter that is greater than the diameter of the wafer, the platen further comprising a leading edge and a trailing edge, wherein the trailing edge is positioned at an opposite end of the substantially planar surface from the leading edge;
• a plurality of fluid channels disposed between the leading and trailing edges of the platen, wherein each of the fluid channels comprises a respective opening defined by the substantially planar surface;
• and
• a segmented platen ring positioned around a portion of the planar surface, wherein each segment may be positioned to be a raised or lowered region of topography.

In a polishing apparatus having a support assembly for supporting a polishing member, wherein a wafer having a diameter is pressed against one side of the polishing member, a platen comprising:

• a substantially planar surface positioned underneath the polishing member opposite the wafer, the substantially planar surface positioned in the support assembly and comprising a diameter that is greater than the diameter of the wafer, the platen further comprising a leading edge and a trailing edge, wherein the trailing edge is positioned at an opposite end of the substantially planar surface from the leading edge;
• a plurality of fluid channels disposed between the leading and trailing edges of the platen, wherein each of the fluid channels comprises a respective opening defined by the substantially planar surface;
• and
• means for providing at least one of a region of altered topography being in the shape of a continuous arc having an arc length less than 180° on a portion of the substantially planar surface of the platen, wherein the arc length of the region of altered topography is relative to a center point of the platen.

In a linear polishing apparatus having a linear belt support assembly for supporting a linear belt, wherein a wafer having a diameter is pressed against one side of the linear belt, a platen comprising:

• a substantially planar surface positioned underneath the linear belt opposite the wafer, the platen further comprising:
• a leading edge and a trailing edge, wherein the trailing edge is positioned at an opposite end of the substantially planar surface from the leading edge;
• and
• a leading half and a trailing half, wherein the leading half is separated from the trailing half by a first diameter extending through a center point of the platen, wherein the first diameter is perpendicular to a second diameter extending from the leading edge to the trailing edge;
• a plurality of fluid channels disposed between the leading and trailing edges of the platen, wherein each of the fluid channels comprises a respective opening defined by the substantially planar surface;
• and
• at least one region of altered topography positioned on a portion of the substantially planar surface, wherein the at least one region of altered topography is located on only one of the leading and trailing halves of the substantially planar surface.