Abstract: The invention is directed to a base-pad for placement under a polishing pad for use with a polishing fluid during a polishing operation, the base-pad having a layer with vertical elongated pores that absorb polishing fluid and that confine absorbed polishing fluid from transport laterally in the base-pad. Micropores in the layer are impermeable to the polishing fluid and permeable to gasses.

Abstract: The invention is directed to a base-pad for placement under a polishing pad for use with a polishing fluid during a polishing operation, the base-pad having a layer with vertical elongated pores that absorb polishing fluid and that confine absorbed polishing fluid from transport laterally in the base-pad. Micropores in the layer are impermeable to the polishing fluid and permeable to gasses.

Abstract: A wafer support member (1), and a method of changing local compressibility of a wafer support member (1) to provide a seal, includes, dispensing a curable sealant material (9) onto a resiliently compressible wafer support member (1), the support member having pores (6) for directing either fluid borne pressure or fluid borne vacuum between the wafer support member (1) and a backside of a wafer to be supported, wicking the sealant material (9) into pores (6) of the wafer support member (1), curing the sealant material (9) to provide a film closing each of the pores (6) that are intercepted by the sealant material (9), to change local compressibility of the edge margin (5) of the wafer support member (1), and provide a seal.

Abstract: A polishing pad is retained on a platen by structures which do not require adhesive. In one embodiment, a polishing pad has a top polishing surface and an undersurface. The undersurface has a surface profile which is configured to interfit with a complementary surface profile on a platen. The surface profile of the undersurface may comprise an array of parallel ridges and grooves.