Driving apparatus, exposure apparatus, and device manufacturing method

#The present invention relates to a driving apparatus, exposure apparatus, and device manufacturing method and, for example, to a driving apparatus which moves an object along a guide surface in the X and Y directions, an exposure apparatus which incorporates the driving apparatus, and a device manufacturing method using the exposure apparatus.

#Typical exposure apparatuses used to manufacture devices such as a semiconductor device include a step & repeat exposure apparatus (also called a stepper) which projects, through a projection optical system, the pattern of a master (reticle or mask) onto a plurality of exposure regions on a substrate and sequentially transfers the pattern onto the plurality of exposure regions while stepping the substrate (e.g., a wafer or glass substrate) and a step & scan exposure apparatus (also called a scanner) which repeats step movement and scanning exposure to sequentially transfer the pattern of a master onto a plurality of exposure regions on a substrate. Among these exposure apparatuses, the step & scan exposure apparatus uses only a light component, of exposure light, relatively close to the optical axis of the projection optical system by restricting the exposure light through a slit. Accordingly, the scanner enables higher-precision exposure of a fine pattern with a larger field angle.

#These exposure apparatuses have a stage apparatus or driving apparatus (wafer stage or reticle stage) which moves a wafer and reticle at high speed and aligns them. When a stage is driven in such an exposure apparatus, the acceleration/deceleration of the stage entails generation of the reaction force of an inertial force. Transmission of this reaction force to a stage surface plate causes vibrations of the stage surface plate. Such vibrations induce natural vibrations in the mechanism of the exposure apparatus, and high-frequency vibrations occur. This may interfere with high-speed, high-precision alignment.

#The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

#FIG. 1 is a graph of the X-Y plane coordinates showing a method of driving a movable portion in a driving apparatus (stage apparatus) of a preferred embodiment of the present invention;

#FIGS. 2A and 2B are graphs showing the driving profiles of an X actuator and Y actuator in the driving apparatus of the preferred embodiment of the present invention;

#A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

#FIGS. 4A and 4B are a plan view and sectional view showing the wafer stage of an exposure apparatus as a preferred embodiment of the present invention which uses the stator of an actuator as a reaction force counter to receive the driving reaction force of a movable element, respectively.

#In FIGS. 4A and 4B, a wafer chuck 31, and bar mirrors 50 and 51 for position measurement are provided on a top plate 30. The wafer chuck 31 vacuum-chucks and holds a wafer serving as an object to be aligned. The bar mirrors 50 and 51 reflect measurement light from a laser interferometer (not shown). The top plate 30 levitates in non-contact to an X-Y slider 38 by a light weight compensator (not shown) which uses a magnet and has six degrees of freedom in six axial directions. The top plate 30 is finely driven in six axial directions (X, Y, and Z directions and their rotational directions) by an actuator which generates a driving force between the top plate 30 and the X-Y slider 38. Two linear motors in the X direction, one linear motor in the Y direction, and three linear motors in the Z direction are provided as actuators for fine moving in six axial directions. If the two X-direction fine moving linear motors are driven in opposite directions, the top plate 30 can be driven about the Z-axis (θ direction). By adjusting the driving forces of the three Z-direction fine moving linear motors, the top plate 30 can be driven about the X-axis (ωX direction) and about the Y-axis (ωY direction). A coil serving as the stator of the fine moving linear motor is provided on the side of the X-Y slider 38, and a permanent magnet serving as the movable element of the fine moving linear motor is provided on the side of the top plate 30.