An electrostatic chuck to minimize an arc and a glow discharge during processing of a semiconductor substrate is provided, In one aspect, an electrostatic chuckin a processing chamber includes a body having a first hole for providing a cooling gas to a backside of a substrate to control a temperature of the substrate, an inner electrode for generating an electrostatic force and a dielectric layer. A ceramic block is tightly inserted into a first hole and has a second hole connected to the first hole. A third hole formed through the dielectric layer is connected to the first hole and the second hole. The cooling gas is provided to the backside of the substrate through the first hole or the second hole. Since the first hole is covered with the ceramic block, the generation of an arc or a glow discharge inside the first hole may be minimized, thereby preventing damage to the electrostatic chuck and improving production yields.