Polishing apparatus

Abstract

The present invention relates to a polishing apparatus for polishing an object to be polished (substrate) such as a semiconductor wafer to a flat mirror finish. The polishing apparatus includes a polishing table configured to support a polishing pad, a polishing head having a top ring configured to press an object to be polished against the polishing pad while the object to be polished is rotated, and a dresser head having a dresser configured to dress the polishing pad. The polishing apparatus has a head cover having a purge gas introducing unit configured to introduce a purge gas into the head cover and an exhausting unit configured to exhaust the interior of the head cover. The pressure in the head cover is set to a pressure level slightly higher than the pressure outside the head cover, and main components of the polishing head are housed in the head cover.

Dependencies are inferred from the claim text.