Abstract: A servo control system to control a position of an object supported by a movable support includes a first measurement system to measure a position of the movable support, a comparative device to provide an error signal based on the comparison between a measured movable support position and a desired movable support position, a controller unit to provide a control signal based on the error signal, and an actuator configured to actuate the movable support based on the control signal. The servo control system further includes a slip compensation device to compensate a slip between the object and the movable support, the slip compensation device including a second measurement system to measure an object position with respect to the movable support, and an addition device to add a slip compensation signal to the measured movable support position or the error signal based on the measured object position.

Abstract: A substrate for use in a lithographic projection apparatus. The substrate includes a sealing coating that covers at least a part of a first interface between two layers on the substrate, or between a layer and the substrate, and does not extend to a central portion of the substrate.

Abstract: A method of aligning a template and a substrate for imprint lithography involves using a mask pattern of the template and a luminescent marker pattern of the substrate, the method including aligning the template mask pattern and the substrate marker pattern using a radiation intensity measurement of radiation emitted by the luminescent marker pattern and having passed the template mask pattern. The mask pattern and the luminescent marker pattern may each be shaped to provide a turning point in the intensity of detected radiation emitted from the marker pattern, and passing through the mask pattern to a detector, as a function of relative displacement at the aligned position. The displacement of the template and substrate may be aligned by identifying the turning point in radiation intensity. The marker pattern may be fluorescent with the emitted radiation excited by a radiation source.

Abstract: A projection system (PS) is provided that includes a sensor system (20) that measures at least one parameter that relates to the physical deformation of a frame (10) that supports the optical elements (11) within the projection system (PS), and a control system (30) that, based on the measurements from the sensor system (20), determines an expected deviation of the position of the beam of radiation projected by the projection system (PS) that is caused by the physical deformation of the frame (10).

Abstract: An optical arrangement, in particular a projection exposure apparatus (1) for EUV lithography, includes: a housing (2) that encloses an interior space (15); at least one, in particular reflective, optical element (4 to 10, 12, 14.1 to 14.6) that is arranged in the housing (2); at least one vacuum generating unit (3) for generating a vacuum in the interior space (15) of the housing (2); and at least one vacuum housing (18, 18.1 to 18.10) that is arranged in the interior space (15) of the housing (2) and that encloses at least the optical surface (17, 17.1, 17.2) of the optical element (4 to 10, 12, 14.1 to 14.5), wherein a contamination reduction unit is associated with the vacuum housing (18.1 to 18.10), which contamination reduction unit reduces the partial pressure of contaminating substances, in particular of water and/or hydrocarbons, at least in close proximity to the optical surface (17, 17.1, 17.2) in relation to the partial pressure of the contaminating substances in the interior space (15).

Abstract: A lithographic projection apparatus according to one embodiment of the invention includes a projection system having a plurality of optical elements or sensors mounted on a frame. The frame includes support portions made of a material (e.g. a glass ceramic) having a coefficient of thermal expansion of less than or approximately equal to 0.1×10−6 K−1.