A substrate holder, for a lithographic apparatus, having a main body, a plurality of support elements to support a substrate and a seal unit. The seal unit may include a first seal positioned outward of and surrounding the plurality of support elements. A position of a substrate contact region of an upper surface of the first seal may be arranged at a distance from the plurality of support elements sufficient enough such that during the loading/unloading of the substrate, a force applied to the first seal by the substrate is greater than a force applied to the plurality of support elements by the substrate. A profile of the contact region, in a cross section through the seal, may have a shape which is configured such that during the loading/unloading of the substrate, the substrate contacts the seal via at least two different points of the profile.

A method includes generating extreme ultraviolet (EUV) light. The EUV light is gathered onto a first region of a first optical reflector by using a collector. A second region of the first optical reflector is free from incidence of the EUV light when the EUV light is reflected onto the first region. The EUV light is reflected to a reticle by using the first optical reflector, so as to impart the EUV light with a pattern. The first optical reflector is rotated such that the EUV light is reflected onto the second region in a first time period and the EUV light is reflected onto the first region in a second period. The first region is free from incidence of the EUV light in the first time period, and the second region is free from incidence of the EUV light in the second time period.

A method of controlling a temperature of the semiconductor device includes operating an semiconductor apparatus; maintaining a temperature of a vessel of the semiconductor apparatus with a first cooling output by a cooling controller; heating the vessel for removing a material on the vessel; transferring a first signal, by a converter, to the cooling controller when heating the vessel; and reducing the first cooling output to a second cooling output by the cooling controller base on the first signal.

A system for mitigating damage to optical elements caused by vacuum ultraviolet (VUV) light exposure is disclosed. The system includes a light source configured to generate VUV and a chamber containing one or more gaseous fluorine-based compounds of a selected partial pressure. The system includes one or more optical elements. The one or more optical elements are located within the chamber and are exposed to the one or more gaseous fluorine-based compounds. The VUV light generated by the light source is of sufficient energy to dissociate the fluorine-based compound within the chamber into a primary product.

A difficulty of contamination interfering with a grid plate positional measurement system is addressed. In one embodiment contamination is prevented from coming into contact with the grating or the sensor. In an embodiment, surface acoustic waves are used to detach contamination from a surface of the grating or sensor.

A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, comprising at least one housing comprising at least one internal wall, at least one optical component arranged within at least one chamber defined at least in part by the at least one internal wall and configured to receive a radiation beam and a cooling apparatus arranged to cool at least a portion of the at least one internal wall to a temperature below that of the at least one optical component.

In an extreme ultraviolet light generating apparatus, the film thickness of debris adhering to a surface of a component can be measured easily without need of large-scale removal of the component disposed in the chamber. The extreme ultraviolet light generating apparatus includes a chamber in which a droplet made of a target material is irradiated with a laser beam and extreme ultraviolet light is generated, an EUV light collector mirror that is an optical element disposed in the chamber, and a measurement device movable along a surface of the EUV light collector mirror and configured to measure the film thickness of the target material adhering to the surface.

An objective lens protection device, objective lens system and lithographic device. The objective lens protection device includes a main structure provided with, oppositely disposed, an air supply unit and extraction unit. The air supply unit is used to output air. The extraction unit extracts air output by the air supply unit to form at least one layer of air curtain between the air supply unit and extraction unit. The objective lens protection device can effectively control the flow rate of wind discharge, controlling wind in a laminar flow state and ensuring uniform flow field of the air curtain, and can effectively block organic matters volatilized from the bottom up, eliminate opportunity for a direct contact of the organic matters with the lens, and prevent objective lens from contamination by the volatilization of the organic matters of photoresist, thus ensuring the imaging quality of the objective lens.

An extreme ultraviolet (EUV) lithography system includes an extreme ultraviolet (EUV) radiation source to emit EUV radiation, a collector for collecting the EUV radiation and focusing the EUV radiation, a reticle stage for supporting a reticle including a pellicle for exposure to the EUV radiation, and at least one sensor configured to detect particles generated due to breakage of the pellicle.

Methods and systems are described for reducing particles in the vicinity of an electrostatic chuck (300) in which a cleaning reticle or substrate (320) is secured to the chuck, the cleaning reticle or substrate having surfaces partially devoid of conductive material so that an electric field from the chuck can pass through to a volume adjacent the substrate to draw particles (360) in the volume to the surface of the substrate. Voltage supplied to the chuck may have an alternating polarity to enhance the attraction of particles to the surface.