Flatmotor device and exposure device

Abstract

To provide a flat motor device capable of suppressing a thermal effect on a peripheral environment. When currents are supplied to armature coils 34 confronting a pole unit 40, a wafer stage WST is driven along a moving surface 32a by electromagnetic force. With this operation, the armature coils 34, to which the respective currents are supplied, generate heat. The armature coils 34 are disposed in the interior of a base 32 along the moving surface. A first fluid passage 62, in which a first fluid flows in a laminar flow state, is disposed to the armature coils on the moving surface side thereof and a second fluid passage 64, in which a second fluid flows in a transition flow state, is disposed thereto on the side opposite to the moving surface, respectively. Therefore, a temperature boundary layer is formed in the flow of the first fluid, whereby the transmission of the heat of the armature coils 34 to the moving surface is effectively prevented as well as the heat can be effectively removed from the armature coils 34 by the second fluid by an increase in the heat transfer coefficient between the second fluid and a stator yoke 58.

Dependencies are inferred from the claim text.