Patent attributes
An etching apparatus includes a reaction chamber having an internal space; an upper electrode in the reaction chamber; a fixing chuck in the internal space of the reaction chamber and below the upper electrode; an electrostatic chuck above the fixing chuck and on which a wafer is configured to be placed; a focus ring surrounding the electrostatic chuck; and a plurality of sealing members configured to seal cooling gas provided to the focus ring and being in contact with the focus ring. The plurality of sealing members may be formed of a porous material. Each of the plurality of sealing members may include a body portion and an outer surface surrounding the body portion. Only the body portion may include voids and the outer surface may be smooth and free of voids.