A substrate holding system having a chuck for vacuum attraction and electrostatic attraction of a substrate. The system includes a ring-like rim for carrying a substrate thereon, a plurality of first protrusions disposed inside the rim, for carrying the substrate thereon, and a plurality of second protrusions disposed inside the rim, for carrying the substrate thereon. A substrate carrying surface area of at least one first protrusion is smaller than a substrate carrying surface area of at least one second protrusion and a smallest interval between the first protrusions is smaller than a smallest interval between the second protrusions. Also included are an exhaust system for exhausting a clearance between the chuck and the substrate, an electrode for electrostatic attraction, a power supplying system for supplying power to the electrode, a measuring system for measuring a pressure in the clearance, and a control system for controlling the power supply.