Abstract: A plasma process apparatus includes a chamber in which a plasma process is performed, an electrostatic chuck which supports a wafer inside the chamber and comprises a first portion and a second portion disposed on the first portion, a first electrode disposed inside the electrostatic chuck, a second electrode which is spaced apart from the first electrode inside the electrostatic chuck, surrounds the first electrode in a plane defined by the first direction and a second direction perpendicular to the first direction, and is disposed on the same plane as the first electrode, a power supply configured to apply a voltage to each of the first electrode and the second electrode, a plurality of cooling gas supply lines which penetrates the electrostatic chuck in a third direction perpendicular to the first and second directions and is configured to provide a cooling gas to the wafer.