An apparatus for an etching process includes a chamber, a plasma generator disposed in the chamber, a stacked structure disposed in the chamber to support a substrate thereon and including an electrode plate and an insulation coating layer on the electrode plate, electrode rods inserted into through holes of the stacked structure to penetrate through the stacked structure, directly contacting the substrate and spaced apart from sidewalls of the through holes of the stacked structure, at least one DC pulse generator generating a DC pulse to the electrode plate and the electrode rods, first connection lines connecting the DC pulse generator to the electrode rods, and at least one second connection line connecting the DC pulse generator to a lower portion of the electrode plate.