The unit consists of drive mechanisms, an encapsulated precision ball screw, and a stepper motor with incremental linear encoder. The anodized-aluminum table weighs less than 10 kg and offers speeds to 100 mm/sec with accelerations of 500 mm/sec. The stage also includes a stationary terminal and integrated cables for motor, measuring system, and vacuum connectors for chucks. For simplified loading and unloading of wafers, the stage drives 40 mm to the left or right asymmetric to the optical axis.