Substrate holding apparatus

A substrate holding apparatus for holding a substrate to be polished and pressing the substrate against a polishing surface, said substrate holding apparatus comprising:

• a top ring body for holding a substrate;
• an elastic pad to be brought into contact with the substrate;
• and
• a contact member including
• (i) an elastic member to be brought into contact with said elastic pad,
• (ii) a holding member for detachably holding said elastic member, and
• (iii) a protrusion radially protruding from a circumferential edge of said elastic member on a lower surface of said elastic member.

A substrate holding apparatus for holding a substrate to be polished and pressing the substrate against a polishing surface, said substrate holding apparatus comprising:

• a top ring body for holding a substrate;
• an elastic pad to be brought into contact with the substrate;
• and
• a contact member including
• (i) an elastic member to be brought into contact with said elastic pad, said elastic member having a partially different thickness, and
• (ii) a holding member for holding said elastic member.

A substrate holding apparatus for holding a substrate to be polished and pressing the substrate against a polishing surface, said substrate holding apparatus comprising:

• a top ring body for holding a substrate;
• an elastic pad to be brought into contact with the substrate;
• a compressed air source for providing pressurized air to at least said elastic pad;
• and
• a contact member including
• (i) an elastic member to be brought into contact with said elastic pad, said elastic member having a partially different thickness, and
• (ii) a holding member for holding said elastic member.

A substrate holding apparatus for holding a substrate to be polished and pressing the substrate against a polishing surface, said substrate holding apparatus comprising:

• a top ring body for holding a substrate;
• an elastic pad to be brought into contact with the substrate;
• a ring assembly including
• (i) a ring tube elastic member to be brought into contact with said elastic pad, said ring tube elastic member having a partially different thickness,
• (ii) a ring tube holder for holding said ring tube elastic member, and
• (iii) a pressure chamber defined by said ring tube elastic member and said ring tube holder;
• a compressed air source for providing pressurized air to said elastic pad and to said pressure chamber;
• and
• a fluid passage communicating said pressure chamber with said compressed air source.