Abstract: Various configurations of a projection system, of a lithographic apparatus, and of a device manufacturing method are disclosed. According to a disclosed configuration, the projection system is configured to project a patterned radiation beam onto a target portion of a substrate. The projection system includes an optical element having a first face and a second face. The first face is configured to be exposed to an external gaseous environment connected to the outside of the lithographic apparatus. The second face is configured to be exposed to an internal gaseous environment, the internal gaseous environment being substantially isolated from the external gaseous environment. The projection system further includes a pressure compensation system configured to adjust the pressure in the internal gaseous environment in response to a change in pressure in the external gaseous environment or a pressure differential between the internal gaseous environment or the external gaseous environment.

Abstract: A method for filtering a fluid to obtain a fluid having a known purity is described. The fluid is filtered with a filtration system, and upstream of a final filtration stage of the filtration system, a purity of the fluid is measured. A purity of the fluid filtered by the filtration system is determined by correcting the measured purity with a filtration behavior of the final filtration stage. In an embodiment, the fluid comprises an ultra pure water for use as an immersion liquid in a lithographic apparatus.

Abstract: An immersion lithographic apparatus is provided with a liquid confinement structure which defines at least in part a space configured to contain liquid between the projection system and the substrate. In order to reduce the crossing of the edge of the substrate which is being imaged (which can lead to inclusion of bubbles in the immersion liquid), the cross-sectional area of the space in a plane parallel to the substrate is made as small as possible. The smallest theoretical size is the size of the target portion which is imaged by the projection system. In an embodiment, the shape of a final element of the projection system is also changed to have a similar size and/or shape in a cross-section parallel to the substrate to that of the target portion.

Abstract: An immersion type lithographic apparatus includes an immersion system configured to at least partially fill an immersion space with an immersion liquid. The apparatus also includes an indicator configured to indicate whether a part of the immersion system should be cleaned and a cleaning liquid supply system configured to supply a cleaner to the part of the lithographic apparatus. The cleaner is at least one of a plurality of different cleaners. Each cleaner or combination of cleaners is configured to clean a different type and/or level of contamination in the part of the lithographic apparatus. The apparatus also includes a controller configured to control which of the plurality of cleaners is provided to the part of the lithographic apparatus, based on an indication received from the indicator.

Abstract: In an immersion lithographic apparatus, bubble formation in immersion liquid is reduced or prevented by reducing a gap size or area on a substrate table and/or covering the gap.

Abstract: An immersion lithographic apparatus has adaptations to prevent or reduce bubble formation in one or more gaps in the substrate table by preventing bubbles escaping from the gap into the beam path and/or extracting bubbles that may form in the gap.

Abstract: An apparatus configured to de-gas a liquid includes a semi-permeable membrane having a first side on which the liquid is provided; and (i) a vaporizer configured to provide vapor of the liquid to a second side of the membrane; or (ii) a gas inlet configured to provide a gas to the second side of the membrane, the gas adapted to dissociate when dissolved in the liquid and an ion exchanger for the liquid downstream of the semi-permeable membrane.

Abstract: An immersion lithographic apparatus has adaptations to prevent or reduce bubble formation in one or more gaps in the substrate table by preventing bubbles escaping from the gap into the beam path and/or extracting bubbles that may form in the gap.

Abstract: An immersion lithographic apparatus has adaptations to prevent or reduce bubble formation in one or more gaps in the substrate table by preventing bubbles escaping from the gap into the beam path and/or extracting bubbles that may form in the gap.

Abstract: A porous member is used in a liquid removal system of an immersion lithographic projection apparatus to smooth uneven flows. A pressure differential across the porous member may be maintained at below the bubble point of the porous member so that a single-phase liquid flow is obtained. Alternatively, the porous member may be used to reduce unevenness in a two-phase flow.

Abstract: A lithographic apparatus is disclosed including a liquid supply system configured to at least partly fill a space between the projection system and the substrate with a liquid, an outlet configured to remove a mixture of liquid and gas passing through a gap between a liquid confinement structure of the liquid supply system and the substrate, and an evacuation system configured to draw the mixture through the outlet, the evacuation system having a separator tank arranged to separate liquid from gas in the mixture and a separator tank pressure controller, connected to a non-liquid-filled region of the separator tank, configured to maintain a stable pressure within the non-liquid-filled region.

Abstract: A porous member is used in a liquid removal system of an immersion lithographic projection apparatus to smooth uneven flows. A pressure differential across the porous member may be maintained at below the bubble point of the porous member so that a single-phase liquid flow is obtained. Alternatively, the porous member may be used to reduce unevenness in a two-phase flow.

Abstract: A lithographic apparatus is disclosed including a liquid supply system configured to at least partly fill a space between the projection system and the substrate with a liquid, an outlet configured to remove a mixture of liquid and gas passing through a gap between a liquid confinement structure of the liquid supply system and the substrate, and an evacuation system configured to draw the mixture through the outlet, the evacuation system having a separator tank arranged to separate liquid from gas in the mixture and a separator tank pressure controller, connected to a non-liquid-filled region of the separator tank, configured to maintain a stable pressure within the non-liquid-filled region.

Abstract: A lithographic projection apparatus is disclosed in which measures are taken to prevent or reduce the presence of bubbles in liquid through which the projection beam radiates. This may be done, for example, by ensuring that a gap between a substrate and a substrate table is filled with immersion liquid or by causing a localized flow radially outwardly from the optical axis in the vicinity of the edge of the substrate.

Abstract: In an immersion lithographic apparatus, bubble formation in immersion liquid is reduced or prevented by reducing a gap size or area on a substrate table and/or covering the gap.

Abstract: A method for filtering a fluid to obtain a fluid having a known purity is described. The fluid is filtered with a filtration system, and upstream of a final filtration stage of the filtration system, a purity of the fluid is measured. A purity of the fluid filtered by the filtration system is determined by correcting the measured purity with a filtration behavior of the final filtration stage. In an embodiment, the fluid comprises an ultra pure water for use as an immersion liquid in a lithographic apparatus.

Abstract: A member is provided to prevent immersion liquid ingress to a gap between components or to adhere to at least one component to provide a surface to a feature of an immersion system. The member has a plastic sealing portion that is adhered to the component(s). The plastic sealing portion is opaque to DUV radiation. It may be resistant to degradation through exposure to DUV radiation. It may have a liquid phobic coating or property.

Abstract: In an immersion lithographic apparatus, bubble formation in immersion liquid is reduced or prevented by reducing a gap size or area on a substrate table and/or covering the gap.

Abstract: In an immersion lithographic apparatus, bubble formation in immersion liquid is reduced or prevented by reducing a gap size or area on a substrate table and/or covering the gap.

Abstract: A lithographic projection apparatus is disclosed in which measures are taken to prevent or reduce the presence of bubbles in liquid through which the projection beam radiates. This may be done, for example, by ensuring that a gap between a substrate and a substrate table is filled with immersion liquid or by causing a localized flow radially outwardly from the optical axis in the vicinity of the edge of the substrate.