Abstract: Provided is a substrate supporting apparatus with improved durability. The substrate supporting apparatus includes a body configured to support a substrate and formed of a dielectric substance; a heat transfer medium supply hole installed to penetrate the body; a first electrostatic electrode disposed in the body; and a second electrostatic electrode disposed in the body, located on the first electrostatic electrode, and electrically connected to the first electrostatic electrode.

Abstract: Provided is an apparatus for a substrate supporting apparatus fixing a focus ring without using a clamp ring. The substrate supporting apparatus comprise a supporting plate for supporting a substrate; a side ring arranged to surround at least a part of a side surface of the supporting plate and including a first through hole; a focus ring arranged on the side ring and including a first circulation channel for circulation of a first temperature control fluid and a second through hole connecting the first circulation channel and a bottom surface therein; and a coupling bolt fixed to the focus ring penetrating through the first through hole and the second through hole from below the side ring and fixing the side ring and the focus ring to each other.

Abstract: Provided are a wafer support unit, in which a dam is installed outside an O-ring to prevent the O-ring from being etched, and a wafer treatment system including the wafer support unit. The wafer treatment system includes: a housing; a shower head introduces a process gas for etching a wafer into the housing; and a support unit includes an electrostatic chuck on which the wafer is mounted, a base supporting the electrostatic chuck, and a focus ring installed on side surfaces of the electrostatic chuck, wherein the support unit includes: a fixing component which fixes the focus ring to the base; a sealing component which is disposed between the focus ring and the base to seal a circumference of a fastening component; and a dam component which is installed outside the sealing component to prevent the sealing component from being etched by the process gas.