Substrate holding apparatus

摘要

The present invention relates to a substrate holding apparatus for holding a substrate to be polished and pressing the substrate against a polishing surface. The substrate holding apparatus comprises a top ring body (2) for holding a substrate, an elastic pad brought into contact with the substrate, and a support member (6) for supporting the elastic pad. The substrate holding apparatus further comprises a contact member mounted on a lower surface of the support member and disposed in a space formed by the elastic pad and the support member. The contact member (8,9) has an elastic membrane brought into contact with the elastic pad. A first pressure chamber (24,25) is defined in the contact member, and a second pressure (22,23) chamber is defined outside of the contact member. The substrate holding apparatus further comprises a fluid source (120) for independently supplying a fluid into or creating a vacuum in the first pressure chamber (24,25) and the second pressure chamber (22,23).