Patent ID: 7916447

Claim:
An electrostatic chuck for electrostatically attracting a substrate which is rectangular when viewed in a planar view, and which has a longer side and a shorter side, said electrostatic chuck comprising a plurality of rod-like electrodes having shorter sides and longer sides, wherein shorter sides of each of said rod-like electrodes are oriented toward outside the electrostatic chuck, and longer sides of each of the rod-like electrodes are parallel to longer sides of adjacent rod-like electrodes, said electrostatic chuck further comprising means for mounting the rectangular substrate on the electrostatic chuck, so that, when the rectangular substrate is mounted on the substrate mounting surface, the rod-like electrodes are disposed along an edge portion of the rectangular substrate to be treated so that one of said shorter sides of each of said rod-like electrodes extends in parallel to a longer side of said rectangular substrate, wherein said rod-like electrodes are comprised of rod-like base materials, wherein cross-sections with respect to a vertical cut-through of said rod-like base materials are in stepped shapes, and wherein said rod-like electrodes are arranged with a predetermined gap (clearance) between adjacent rod-like electrodes, said means comprising configuring the rod-like electrode and locating them relative to one another to form a substrate mounting surface comprised of the rod-like electrodes, which substrate mounting surface has overall rectangular dimensions with a longer side equal to or greater in length than the length of the rectangular substrate and with a shorter side equal to or greater in length than the shorter side of the rectangular substrate.