ALIGNMENT DEVICE AND LITHOGRAPHIC APPARATUS PROVIDED WITH SUCH A DEVICE

摘要

A device is described for aligning a first object provided with a first alignment mark (P) with respect to a second object provided with a second alignment mark (M), which marks have a periodical structure and are imaged onto each other. By selecting beam portions from the radiation from the first alignment mark (P) with the aid of an order diaphragm (55'), which beam portions are deflected through larger angles, the sensitivity of the device to errors can be decreased. Such a device may be used to great advantage in a lithographic apparatus.