Abstract: A vacuum processing system has a process chamber with a rotating member, such as a magnetron in a physical vapor deposition (PVD) chamber, disposed near a surface, such as a target in a PVD chamber. The rotating member and the surface are cooled by a cooling fluid. The rotational motion of the rotating member induces the cooling fluid to circulate around the rotating member and between the surface and the rotating member, thus efficiently cooling the rotating member and the surface with a quickly flowing fluid.The rotating member has a fluid conduit extending from the rotational center of the rotating member to the outer edge of the rotating member. The cooling fluid inside the fluid conduit is subject to a centrifugal force under the action of the rotational motion, so that the cooling fluid is induced to flow from the rotational center to the outer edge, thus forcing the cooling fluid to circulate.