Abstract: Two-dimensionally balanced positioning device with two object holders, and lithographic device provided with such a positioning device.A positioning device (3, 97, 179) with a first displacement unit (25, 189) for displacing a first object holder (11, 181) and a second displacement unit (27, 191) for displacing a second object holder (13, 183). The object holders can be displaced by the positioning device alternately from a measuring position into an operational position and can be displaced by the respective displacement units independently of one another in the measuring position and in the operational position.The displacement units are provided with force actuators which each have a first part (47, 49; 117, 119; 215, 217) which is coupled to the relevant object holder and which is displaceable under the influence of a driving force relative to a second part (59, 61; 133, 135, 137, 139; 219, 221) which is fastened to a balancing unit (69, 149, 205) which is common to the two displacement units.

Abstract: A lithographic device includes a machine frame which supports a substrate holder, a focusing system and a mask holder in a vertical direction. The substrate holder is displaceable parallel to a horizontal X-direction and a horizontal Y-direction perpendicular to the X-direction by a first positioning device, and the mask holder is displaceable parallel to the X-direction by a second positioning device. The substrate holder and the mask holder are displaced synchronously parallel to the X-direction during exposure of a semiconductor substrate. The second positioning device is capable of positioning the mask holder also parallel to the Y-direction and of rotating it about a vertical axis of rotation. Therefore, a displacement of the mask holder has a parallelism to the X-direction which is determined by a positioning accuracy of the second positioning device and which is not adversely affected by a deviation from parallelism and straightness of a guide of the second positioning device.